First, download the actual non-aplha release of LINQ to XSD and extract it.  You will need to have .NET 3.5 installed to run LINQ to XSD.  The project itself is a Visual Studio 2010, .NET 4.0 project.  You should be able to change it to .NET 3.5 with no problems.  I’m not sure about using .NET 2.0.   I still assume these steps should work with Mapguide Open Source 2.2 given its pretty much the same thing as MGE 2011.  Please let me know if you try it and that is not the case.

Building the classes

Last time around we had to mess around with Visual Studio projects, building temporary code, finding and extracting that code from temporary files.  This time around, we’re given a nice little executable that can be run in a batch file.   I’ve posted a copy of my batch file below but it was simply made using a dir /b > CreateMapguideNetObjects.cmd in the Mapguide server schema folder (which by default is to c:\Program Files\Autodesk\MapGuideEnterprise2011\Server\Schema) .  I then edited that file with a text editor that support macros and removed the following schema files:

• FdoProviderCapabilities-1.0.0.xsd
• LoadProcedure-1.0.0.xsd
• LoadProcedure-1.1.0.xsd
• LayerDefinition-1.0.0.xsd
• LayerDefinition-1.1.0.xsd
• LayerDefinition-1.2.0.xsd
• SiteInformation-1.0.0.xsd
• SiteVersion-1.0.0.xsd
• SymbolDefinition-1.0.0.xsd
• WebLayout-1.0.0.xsd

These files are deprecated object definitions from previous Mapguide releases.  In the end each line in the batch file looks a little like this:

LinqToXsd ApplicationDefinition-1.0.0.xsd /filename:ApplicationDefinition.cs

Executing the batch file will create a number of C# files containing appropriately named classes.

Setting up your project

At this point you should be able to fire up Visual Studio and create a new C# project.   If you have an existing project from a previous version of Mapguide its good to start fresh.  Also, don’t try this in an existing solution that is dependant on the project that contains the Mapguide objects.  This will just result in a bunch of extra screwing around to avoid compiler errors from missing code during the process.    This time around its a lot easier.  Create a new DLL project.  Add a reference to the Xml.Schema.Linq.dll file that was included with LinqToXsd.exe.   Add a reference to the following Mapguide dlls:

• OSGeo.Mapguide.Foundation
• OSGeo.Mapguide.Geometry
• OSGeo.Mapguide.MapguideCommon
• OSGeo.Mapguide.PlatformBase
• OSGeo.Mapguide.Web

You’ll also need to ensure that the appropriate unmanaged assemblies are available in the calling applications bin folder when you go to run this stuff. 

Next place all of the generated C# files in the new project.  Once you build you’re going to see a ton of errors.  We’ll clean those up.

To resolve a lot of these errors I did a global search and replace on “global::” and replaced it with nothing.  Also, I wrapped each class in a unique wrapper classes to prevent duplicate type errors.  Finally, the case issue with DataType was still an issue – and I resolved it by changing the case on DataType to be Datatype:

   1: public string DataType {

   2: public string Datatype {

For a complete view of the changes I made do a file compare between the code in the attached zip file and your newly generated code.

<insert 3 week gap here, wherein I had a hell of a time getting MGE 2011 installed and properly licensed so that I could actually test this newly created code, oh and I also went on vacation for a few days too =)/>

And back.  The best part about this is that it seems ALL my old RADE code just worked with upgraded basic layouts after changing it to look for the object definitions within the new wrapper classes.   Now I just need to add support for flexible layouts and we’ll be laughing.

The Code

Please note – I didn’t rebase the code.  It’s all in the RADE.MGE namespace.  If you would like to use it, feel free to re-base it – or just leave it as is.  Also, if you create any unit tests or enhancements and would like to share them – please feel free!  

As I update the project myself, or receive updates I will update this file.

. 

Finally, the example code I posted long ago will still work with this new project.  Perhaps one day, I’ll post some fancy new code in C# =)

Hope this comes in handy, I welcome your comments.

   1: Line: 2

   2: Char: 2498

   3: Error: 'OpenLayers.Lang' is null or not an object

   4: Code: 0

Loading the web tier on the Mapguide server worked fine.  Very odd.  I ended up doing a file comparison between the two web tiers and noticed the only significant difference was this in the web.config:

   1: <staticContent>

   2:     <mimeMap fileExtension=".json" mimeType="application/json" />

   3: </staticContent>

Adding this tag to IIS 7 on Vista resulted in an error, the tag must be something new in IIS 7.5.  However, after manually adding the mime type mapping to the server – my flexible layout now loads perfectly on the local Vista web tier.

This mime type mapping can be added on either the virtual directory, or the server level.  I chos to add it to the server.  Either way, to add it select the appropriate level in IIS manager.  In the right hand window double click “Mime Types”.  Click Add and you can enter the .json extension and the mime type.  Once this is added, Vista/IIS7 was now properly serving out flexible layers

After installing Mapguide 2010 (both server and web tier) on a server running 2009 and updating the license manager appropriately, you’ll notice that the service is not running.  Attempts to start the service will result in an error message logged in the Windows Application Log that looks a little bit like this:

The description for Event ID ( 0 ) in Source ( MapGuide Enterprise 2010 Server ) cannot be found. The local computer may not have the necessary registry information or message DLL files to display messages from a remote computer. You may be able to use the /AUXSOURCE= flag to retrieve this description; see Help and Support for details. The following information is part of the event: Port 2801 is not available, please try using a different port.

So we need to setup one of the Mapguide installations to use a different set of ports.  I’ve chosen to modify the behavior of Mapguide 2010, though these changes could be made for Mapguide 2009 instead.   For this process we’ll need three free ports.  For simplicity its nice to keep these ports sequential.  You will need to ensure that the ports you choose are available on your system.

First we need to edit the serverconfig.ini in the C:\Program Files\Autodesk\MapGuideEnterprise2010\Server\Bin folder.   First lets change the Port in the AdministrativeConnectionProperties section from 2800 to lets say 3800.   Next in the ClientConnectionProperties section change the port to 3801.  Finally change the port in SiteConnectionProperties to 3802.

Next we need to edit the webconfig.ini in the C:\Program Files\Autodesk\MapGuideEnterprise2010\WebServerExtensions folder.  We need to update the port numbers in this config to match the numbers in the server config.  Remember the web config is the client that will usually be consuming the server service.  Finally, as the configuration settings for the web tier may be cached you should restart IIS using iisreset.exe.  This will clear the cached port configurations and Mapguide Studio / Mapguide Administration will now work properly.

Once that is done, the 2009 repository can be migrated to 2010 by following the steps included in the Help/MGE2010UpgradingWindows.htm file on your installation disc/folder.

PHP Problems

Once MGE 2010 has been installed I had a problem with PHP.  Multiple PHPs can be bad news.  I’ve found that running both MGE 2009 and 2010 using the PHP provided with 2010 seems to do the trick.  First you will need to edit the Windows system path.  Update the path variable there to point to the 2010 PHP installation.  If a 2010 path variable exists already – remove the 2009 path.  Next open the IIS manager and ensure that both the MGE 2009 and MGE 2010 virtual directory trees are pointing to the MGE 2010 php extension in the Application Extension Mappings.

Once these changes have been made, do a quick IISreset and you should now be able to login to both the Mapguide admins, as well as have Mapguide Studio connect to the appropriate servers.  Again – this setup could have issues – so consider your environment and needs before configuring a server with both releases of Mapguide.

Remote Web Tiers

If you need to run a shared Mapguide server with web tiers installed on individual development machines don’t forget to set the ports on each development machine.   The Mapguide installer will prompt for the Mapguide server IP address – but the webconfig.ini will need to be updated with the appropriate ports manually.  Not doing do will result in your web tier talking to the 2009 server – and much confusion =)

Finally one note on IP addressees and remote web tiers.  If you plan to use a remote web tier – make sure your Mapguide server is setup using the actual IP address of the server and not 127.0.0.1.  If your Mapguide server is configured with 127.0.0.1, you will get a “Cannot establish connection.” error on the remote web tiers when attempting to create and use a session.  Using real IP addresses (either internal or external) will prevent this error from occurring.

Thanks Autodesk! =)

So instead I have centralized my server resources into a nice VM setup running on my beefy Dell server.  Now, regardless of which machine I use to develop I can still access the same data sets.  This is especially nice when traveling.  Specifically Mapguide Server and web tier are installed on my development web server.  When coding, I will either use my local IIS or the built in Visual Studio web server.  This poses one problem when working with Mapguide.  Referencing the web tier on the shared server from another web server will result in cross site scripting (XSS) errors.  Basically, javascript on one web server cannot access javascript code on another web server, which under most circumstances is a good thing.  When trying to develop using the Mapguide Web API on a central Mapguide server this poses a problem as the web tier API is wholly contained within the virtual directory on another server.  Gotta love when ’security’ jumps up bites us in the behind.

The simple solution to this problem is to install the Mapguide web tier on every development machine.  This will require that each development machine have a web server installed, but chances are that is already the case.  When installing the web tier be sure to have the IP address of the Mapguide server handy as it will needed during the install.  Once the web tier is running locally, reference the local web tier in your URLs and the cross site scripting vulnerabilities go away!  If you’re running the 64 Bit version of Vista on your development machine, check out my post installing the web tier on Vista x64

I did some brief looking around and word on the internets is that the YUI compressor is one of the better compressors out there.  The YUI compressor is an open source java applet.   This *should* work with Mapguide Open, heck this might even be done already in MGOS – but I am only using Enterprise so I cannot confirm, deny, or test this.  

Some of the key things the compressor will do:

1. remove all comments
2. remove all white space and line breaks
3. rename all local variables and parameters to single characters

The YUI compressor should not alter variable values or your logic in any way.

To use the YUI compressor you will need to have Java installed.  Note that if you have the Oracle client installed, you probably have Java already  Once you have Java, you can download a copy of the YUI compressor (I’m going to start referring to it as the YC now…).  If you don’t feel like downloading Java and the YC – I’ve attached the processed files at the bottom of this post.

Lets first look at the javascript shipped with Mapguide Enterprise.  If you browse to your web server extension viewer files (the default location is C:\Program Files\Autodesk\MapGuideEnterprise2009\WebServerExtensions\www\viewerfiles I believe) you will see ten javascript files.  If you choose to process these files on your own please back them up first.  Don’t blame me if you don’t backup your files and something goes wrong =).

Before YC:

Using the YC is simple:

   1: c:\oracle\product\10.2.0\client_1\jdk\bin\java.exe -jar f:\utils\YUICompress\yuicompressor-2.3.6\build\yuicompressor-2.3.6.jar -o comp\browserdetect.js browserdetect.js

Update the paths to Java and the YC as per your environment.  Using the handy dir /B *.js > go.bat I created a batch file of all the javascript files in the viewerfiles folder.  Be sure to run this from a dos window in the viewerfiles folder, or update the paths.  You will also need to create the comp folder in viewerfiles.   Quick cut and pasting created the following batch file:

   1: c:\oracle\product\10.2.0\client_1\jdk\bin\java.exe -jar f:\utils\YUICompress\yuicompressor-2.3.6\build\yuicompressor-2.3.6.jar -o comp\browserdetect.js browserdetect.js

   2: c:\oracle\product\10.2.0\client_1\jdk\bin\java.exe -jar f:\utils\YUICompress\yuicompressor-2.3.6\build\yuicompressor-2.3.6.jar -o comp\contextmenu.js contextmenu.js

   3: c:\oracle\product\10.2.0\client_1\jdk\bin\java.exe -jar f:\utils\YUICompress\yuicompressor-2.3.6\build\yuicompressor-2.3.6.jar -o comp\digitize.js digitize.js

   4: c:\oracle\product\10.2.0\client_1\jdk\bin\java.exe -jar f:\utils\YUICompress\yuicompressor-2.3.6\build\yuicompressor-2.3.6.jar -o comp\hashtable.js hashtable.js

   5: c:\oracle\product\10.2.0\client_1\jdk\bin\java.exe -jar f:\utils\YUICompress\yuicompressor-2.3.6\build\yuicompressor-2.3.6.jar -o comp\initdwfctrl.js initdwfctrl.js

   6: c:\oracle\product\10.2.0\client_1\jdk\bin\java.exe -jar f:\utils\YUICompress\yuicompressor-2.3.6\build\yuicompressor-2.3.6.jar -o comp\legend.js legend.js

   7: c:\oracle\product\10.2.0\client_1\jdk\bin\java.exe -jar f:\utils\YUICompress\yuicompressor-2.3.6\build\yuicompressor-2.3.6.jar -o comp\numfmt.js numfmt.js

   8: c:\oracle\product\10.2.0\client_1\jdk\bin\java.exe -jar f:\utils\YUICompress\yuicompressor-2.3.6\build\yuicompressor-2.3.6.jar -o comp\pngfix_map.js pngfix_map.js

   9: c:\oracle\product\10.2.0\client_1\jdk\bin\java.exe -jar f:\utils\YUICompress\yuicompressor-2.3.6\build\yuicompressor-2.3.6.jar -o comp\sarissa.js sarissa.js

  10: c:\oracle\product\10.2.0\client_1\jdk\bin\java.exe -jar f:\utils\YUICompress\yuicompressor-2.3.6\build\yuicompressor-2.3.6.jar -o comp\wz_jsgraphics.js wz_jsgraphics.js

(*Sorry about the overlap.  I’m working on a new layout and am addressing that in there)

Running that output all of the compressed of the files down somewhat, to pretty significantly.

A quick comparison of one of the function calls:

   1: function MenuData(menuName, arrowHeight, scrollInc, scrollDelay, minSize, iconScrollUp, iconScrollUpDisabled, iconScrollDown, iconScrollDownDisabled, owner, withIFrame, bkColor)

   2: function MenuData(F,H,I,K,E,G,D,J,A,C,B,L)

As you can see – the savings can be significant.

I’m not using the Fusion viewer yet so I did not process those files, but I did check some of the JS in there and each script file had a huge header comment.  It looks like Fusion could also benefit from some compression action.  Please note, I’ve been running my web tier using this script for a day or two.  I’ve not run any serious testing on this code – so try this at your own risk.  You did make that backup I suggested, right?  That said, I have not personally experienced any problems yet.  Also, should you compress your viewerfiles and have problems be sure to try your backups.  Especially before calling your dealer or Autodesk for help. (sorry product support and ADN guys.  Please don’t hate me =] ).

if you would rather not run the YC yourself.

Enjoy!

However, in most cases you’re better off using a form and posting your data up to the server side that way, as the limitations on data are so large you will likely not need to worry about them.  Sometimes, query strings can also show your users just a little too much information – though I’m by no means a proponent of "security through obscurity" hiding a little bit more from your users will keep the curious ones a little more in check =).

When working with Mapguide Enterprise/Mapguide Open Source we need to grab some potentially massive XML strings from the MgMap object and pass these along to the server side for processing.  Take the selection XML from the MgMap object, even a single entity selection can use a significant portion of the characters available in the query string.  On top of that, passing this data via query string requires that the data be URL encoded, using even more of our precious query string characters.

Depending on the design of your application it may not always be feasible to define a hard coded form, or even a form defined server side using ASP.NET.  In some cases (you guessed it – my case) you may want to use javascript and do all the work on the client side to define a form and pass the data long that way.

Well you’re in luck, I found a pretty nice solution (WELL, at least I’m liking it  =]).   I’m kicking myself for not realizing this long ago, but oh well.  So the following javascript function demonstrates how to build, add, populate, and submit a form on the fly using some information from the MgMap object.

   1: function postData()   

   2: {   3: //get the map   

   3: mapObj = GetMap();   

   4:  

   5: //define the new form   

   6: var newForm = document.createElement("form");   

   7: //set the method to POST - the opposite of query strings..   

   8: newForm.method="POST";  

   9:  //add the new form to the current document  

  10:  document.body.appendChild(newForm);  

  11:  

  12:  //lets get some data and add it to the form  

  13:  AddFormElement(newForm, "MapName", oMap.GetMapName());  

  14:  AddFormElement(newForm, "SID", oMap.GetSessionId());  

  15:  //be sure you escape the selection XML - or you will get an error on post about a   

  16:  //"potentially dangerous form value".  Remember on the server side to Server.UrlDecode() it  

  17:  AddFormElement(newForm, "sel", escape(oMap.GetSelectionXML()));  

  18:  

  19:  //lets create our new window  

  20:  var szTarget = "targetWin"  

  21:  newForm.target = szTarget;  

  22:  //set the name/path of the ASPX file you want to process your form with  

  23:  newForm.action = "/url_to_open/file.aspx"  

  24:  

  25:  //open a new window to submit the form to.  Its a good idea to have a blank.htm so you don't get a file not found error  

  26:  var oWin = window.open("blank.htm",szTarget,'menubar=yes, resizable=yes,scrollbars=yes, status=no,toolbar=no,width=300, height=300');  

  27:  

  28:  //give the window focus.  Users like this  

  29:  oWin.focus();  

  30:  

  31:  //submit the form - it will now open in the new window  

  32:  newForm.submit();  

  33:  //remove the form from the document, we're done with it  

  34:  document.body.removeChild(newForm);  

  35:  }  

  36:  

  37:  function AddFormElement(form, elementName, elementVal)  

  38:  {  

  39:      var newElement = document.createElement("<input name='" + elementName + "' type='hidden'/>");  

  40:      newElement.value = elementVal;  

  41:      form.appendChild(newElement);  

  42:      return form;  

  43:  }

On the server side, you can now access this data from ASP.NET using Request.Form, for example Request.Form("MapName") would give you the map name.  Don’t forget when retrieving the selection XML to run that through Server.UrlDecode, or HttpUtility.UrlDecode.

As usual, any comments, bugs, or rotten fruit – send em my way.  Enjoy!

Report looked good.  The results were sorting, checkboxes working.   Wait a minute, I selected the entire map.  There should be more than twenty items returned.  So a quick search of my twelve thousand saved e-mails from the Mapguide Users mailing list turned up what needed to be done.  Fortunately Autodesk added a GenerateFilters call to MgSelection.  This call returns an MgStringCollection of filters.

Basically the solution to this problem is to use GenerateFilters instead of GenerateFilter, and loop through the results.  Each time, appending the returned keys to the complete list.  For example:

   1: Public Shared Function GetSelectedKeysString(ByRef siteConn As MgSiteConnection, _

   2:     ByRef resSvc As MgResourceService, ByVal oMap As MgMap, ByVal SessionId As String, _

   3:     ByVal SelectionXML As String, ByVal layerResID As MgResourceIdentifier, _

   4:     ByVal keyFieldName As String) As String

   5:  

   6:     Dim szKeys As String = ""

   7:     Dim oSel As New MgSelection(oMap)

   8:     oSel.FromXml(SelectionXML)

   9:     Dim curLay As MgLayerBase

  10:     'isolate the layer

  11:     For Each layerItem As MgLayerBase In oSel.GetLayers

  12:         If layerItem.Name = layerResID.Name Then

  13:             curLay = layerItem

  14:         End If

  15:     Next

  16:  

  17:     Dim featSvc As MgFeatureService = siteConn.CreateService(MgServiceType.FeatureService)

  18:     Dim queryOptions As New MgFeatureQueryOptions

  19:     Dim featureClassName As String = curLay.GetFeatureClassName

  20:     'workaround using GenerateFilters and looping through the results as needed

  21:     Dim featureReader As MgFeatureReader

  22:     Dim filters As MgStringCollection = oSel.GenerateFilters(curLay, featureClassName, 20)

  23:     Dim filterCnt As Integer = 0

  24:     While filterCnt < filters.GetCount

  25:         queryOptions.SetFilter(filters.GetItem(filterCnt))

  26:         featureReader = featSvc.SelectFeatures(New MgResourceIdentifier(curLay.GetFeatureSourceId), featureClassName, queryOptions)

  27:         While featureReader.ReadNext

  28:             If szKeys = "" Then

  29:                 szKeys = ConvertPropertyToString(featureReader, keyFieldName)

  30:             Else

  31:                 szKeys &= "," & ConvertPropertyToString(featureReader, keyFieldName)

  32:             End If

  33:         End While

  34:         featureReader.Close()

  35:         featureReader.Dispose()

  36:         filterCnt += 1

  37:     End While

  38:     Return szKeys

  39: End Function

In this code, we get the selection from the MgMap object and then isolate the layer in question.  Then we generate the collection of filters and loop through them.  Each time, adding the appropriate value to the list of keys.  Note the use of ConverPropertyToString, this needs to be used to ensure that the various data types are converted over to string.

.  If you’re looking for a C# example of how to use GenerateFilters one is provided in the source for buffers.aspx.

After making these changes my reports now look all proper! hurray.  Maybe I can hit the sack now?  nahh.

So a data connection was created pointing to the Oracle 10g schema.  This database contained a number of tables containing Lat/Long point geometry entities.  I created a layer pointing to the table in question.  I created a layer pointing to that data connection.  At this point the entities showed up as expected in the both the DWF and the AJAX viewers.  Once again, I could not select any of the entities.  I checked the server logs, no errors were reported.

In troubleshoot mode, I tried just about everything I could think of but nothing would work.  I simplified the theme, created new layers, removed all other layers from them map.  Eventually I created a new layer from another table.  Luckily, the entities on this layer could be selected.  It must be a problem with the underlying data.  On a hunch, I checked the table definitions – specifically looking at primary keys.  The selectable layer had a primary key defined, the problem layer did not.  (Good thing I cannot take credit for creating this source data =))

So, I created a primary key on the problem table, did a touch on the layer definition (opening the definition in Studio and saving it without any changes) and then left for twenty minutes.  I’m thinking there is some sort of caching going within the server, and I’m not sure how it works.  Immediately reloading the map after adding the primary key did not work – the entities were still not selectable.  When I came back – the items in the viewers were now selectable.

So long story short, if again you cannot select map entities using the Autodesk FDO Provider for Oracle ensure that the source table has a primary key defined.  Hopefully this saves someone some grief =)

With Mapguide Enterprise – I may have found a solution.  Recently I created a themed layer for municipalities.  There were twenty five municipalities in a single spatial table.  Each municipality had a unique code.   In an effort to bang these off quickly I added the twenty five municipalities and the filter condition.   Next I entered the twenty five legend labels.

Here is the developer friendly method I came up with creating a somewhat visually appealing color range.  In the first condition I set first set the transparency to 50%.  The transparency affects the resulting color.  Select the color combo and choose "More Colors".  This should bring up the custom color dialog.  First, select one of the "Custom Color" boxes and set the Hue to 0. Next I created a color I wanted to use as my starting shade.

At this point, I saved the color using the "Add to Custom Colors" button.  Your form should look something like this:

Click OK a couple of times and your first condition should be set.  Next I selected my next condition, and clicked the color combo again choosing "More Colors" once again.  This time, select the saved custom color and it should reset the form with the previously saved shade.  At this point I incremented the Hue by 20 to 20.  Click ok a couple of times and repeat.  I was not re-saving my shade, though I suppose that might have made sense.  Each time you repeat this process increase the hue by 20 until you hit the max of 239.

If needed, and you do hit the max hue start the process over starting with another complimentary base shade with a hue of 0. Using a hue increment of 40 might have resulted in more distinct colorations and may be a good idea.

I think it turned out OK, but then again as I stated earlier – I’m color stupid. 

Anyhow, I wanted to share the Pima County Mapguide Color Chart.  I can’t believe I hadn’t found this page sooner.  A fantastic, and crucial reference.   Tons of useful settings for the chart generator.  Show the hex codes for using the colors in HTML, Decimal RGB values for Mapguide Enterprise \ Autocad.  The colors under the Decimal heading are the RGB values – ordered in Red, Green, Blue.  I’ve been using the chart in this config.

Thanks Pima County.  Hopefully, you guys were able to come up with a programmatic method of creating this chart.  I’d hate to be the guy tasked with ‘eyedropping’ all these colors using Photoshop or something.

The decimal values by the way should work with AutoCAD too.

One of my first tasks with Mapguide Enterprise was to build a map on the fly.  There were examples for adding layers to the map programmatically after the viewer had loaded, but this didn’t match the desired flow of my application.  Also, having come from years of Mapguide 6.5 and lower -  I was trying to avoid as much client side automation as possible.  The new Web Tier API was one of the things that excited me the most about Mapguide Enterprise / Mapguide Open Source

I’ve pasted the full, commented code here, as well as attached a solution containing the two projects needed.  Note these projects are Visual Studio 2008 projects.  Please feel free to use this code for learning purposes.  If it helps you out, link back to this article =)

If you choose instead to create a new project, be sure to add a project or DLL reference to the OSGeo.Mapguide.Objects.dll file we created previously .  The project I’ve included here contains both the sample Web Application project, as well as a copy of the .NET objects for Mapguide project.  It should be almost ready for the running.  Also ensure there is a reference to the Microsoft.XML.Schema.Linq namespace added to the project.  Also copy the required .DLL files from the Autodesk provided .NET viewer\bin folder to the web projects bin folder.  I did not include these here as I was not sure of the legality of doing so.

First load up the Sheboygan package into your Mapguide repository.  For the purposes of this example, open the Map definition in Mapguide Studio (or equivalent) and remove all the layers and layer groups from the map.  If you forget to do this you will get a Duplicate Object error when you load up the map.  Once that is done, you are ready to try out the code.

You should be able top unzip the zip and open the MGEDynamicAuthoringSample.sln file with Visual Studio.  Pretty much the only thing you may need to change are the constants to match your machine specific items:

   1: 'set some contants up - webconfig.ini, map viewer url, Map, Layout and Layer locatinos

   2: Private Const gszWebConfig As String = "C:\inetpub\MapGuideEnterprise2009\WebServerExtensions\www\webconfig.ini"

   3: Private Const gszViewerUrl As String = "http://localhost/mapguide2009/mapviewerdwf"

   4: Private Const gszMapResID As String = "Library://Samples/Sheboygan/Maps/Sheboygan.MapDefinition"

   5: Private Const gszLayerFolderResID As String = "Library://Samples/Sheboygan/Layers.Folder"

   6: Private Const gszLayoutResID As String = "Library://Samples/Sheboygan/Layouts/SheboyganAsp.WebLayout"

   7: 'lets run with Administrator for noew to eliminate permission problems.  Update your password as needed, or specify your

   8: 'own credentials if you are comfortable with setting up repository permissions.

   9: Private Const gszMGUser As String = "Administrator"

  10: Private Const gszMGPass As String = "admin"

Once you’ve changed all the needed settings, you should be good to go.  Run the code in Visual Studio and you should now see a map similar to the default Sheboygan map.  The key difference is that all of the layers will exist within the layer group we created programmatically.

Commented Codebehind:

   1: Imports OSGeo.MapGuide

   2: 'we still need to import and use system.xml, but don't really need to use many parts of the XML

   3: 'functionality =)

   4: Imports System.Xml

   5: Partial Public Class _Default

   6:     '' 'So for this example, we're going to use the sheboygan sample package available from 

   7:     '' ' http://mapguide.osgeo.org/download/releases/2.0.x-samples.  Be sure to grab both the 

   8:     '' ' dotnetviewstample.zip as well as the sheboygan.mgp.  Import the package using

   9:     '' ' the mapguide site administrator.  I've tried to use the default resource paths

  10:     '' ' but some tweaking of map will be needed

  11:     '' ' 

  12:     '' ' Open the map definition in Studio, and remove all the layers from Samples/Sheboygan/Maps/Sheboygan.MapDefinition 

  13:     '' ' we're going to add them dynamically    

  14:  

  15:     Inherits System.Web.UI.Page

  16:  

  17:     'set some contants up - webconfig.ini, map viewer url, Map, Layout and Layer locatinos

  18:     Private Const gszWebConfig As String = "C:\inetpub\MapGuideEnterprise2009\WebServerExtensions\www\webconfig.ini"

  19:     Private Const gszViewerUrl As String = "http://localhost/mapguide2009/mapviewerdwf"

  20:     Private Const gszMapResID As String = "Library://Samples/Sheboygan/Maps/Sheboygan.MapDefinition"

  21:     Private Const gszLayerFolderResID As String = "Library://Samples/Sheboygan/Layers.Folder"

  22:     Private Const gszLayoutResID As String = "Library://Samples/Sheboygan/Layouts/SheboyganAsp.WebLayout"

  23:     Private Const gszMGUser As String = "Administrator"

  24:     Private Const gszMGPass As String = "admin"

  25:  

  26:     ''' <summary>

  27:     ''' Page_Load does everything =)  Be sure to copy the dll files from your mapviewernet\bin folder to this projects bin folder.

  28:     ''' I did not include them as that might have violated some autodesk license.    

  29:     ''' </summary>

  30:     ''' <param name="sender"></param>

  31:     ''' <param name="e"></param>

  32:     ''' <remarks></remarks>

  33:     Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

  34:  

  35:         'setup our siteconnection

  36:         Dim siteConnection As New MgSiteConnection

  37:         siteConnection = CreateMGSession(gszMGUser, gszMGPass, gszWebConfig)

  38:         Dim szSessionId As String = siteConnection.GetSite.CreateSession()

  39:  

  40:         'create our connection to the resource service

  41:         Dim resSvc As MgResourceService

  42:         resSvc = siteConnection.CreateService(MgServiceType.ResourceService)

  43:  

  44:         'get or set the resourceid of the map to load - in this case i'm just going to hard code it

  45:         Dim mapResourceID As New MgResourceIdentifier(gszMapResID)

  46:  

  47:         'load the existing map from the libary into an XML document

  48:         Dim mapXML As XmlDocument = GetResourceXML(resSvc, mapResourceID)

  49:  

  50:         'so at this point we have an XML document.  Let's try using our new OSGeo.Mapguide.Object classes

  51:         Dim newMapDefinition As New OSGeo.MapGuide.Objects.MapDefinition

  52:  

  53:         'to load the xml - call the shared/static method of MapDefinition.Parse on the OuterXML of the XMLDocument

  54:         newMapDefinition = OSGeo.MapGuide.Objects.MapDefinition.Parse(mapXML.OuterXml)

  55:  

  56:         'at this point we have a loaded .NET Object containing the map.  Try using Intellisense to see the different methods

  57:         'Lets add a layer group now

  58:  

  59:         'add any needed layer groups to the map.  In this example we're only going to add one.

  60:         Dim szLayerGroupName As String = "NewLayerGroup"

  61:         Dim szLayerGroupAlias As String = "My Layer Group Alias"

  62:         newMapDefinition = AddMapLayerGroup(newMapDefinition, szLayerGroupName, szLayerGroupAlias)

  63:  

  64:         'get or set the resourceid of the folder that contains our layers to add

  65:         Dim layerPath As New MgResourceIdentifier(gszLayerFolderResID)

  66:  

  67:         'so we now have a layer group in our map.  Lets add the layers

  68:         AddFolderOfLayers(resSvc, newMapDefinition, layerPath, szLayerGroupName)

  69:  

  70:         'at this point our map definition is loaded.  Lets convert it back to XML and save it to the session

  71:         Dim newMapDoc As New XmlDocument

  72:         newMapDoc.PreserveWhitespace = True

  73:  

  74:         Dim szXML As String = newMapDefinition.Untyped.ToString

  75:         newMapDoc.LoadXml(szXML)

  76:  

  77:         'create our 'new' resourceID in the session repository

  78:         Dim newMapResourceID As New MgResourceIdentifier("Session:" & szSessionId & "//" & mapResourceID.GetName() & "." & MgResourceType.MapDefinition)

  79:  

  80:         'save the newly created map in the session repository

  81:         CreateSessionResource(resSvc, newMapDoc, szSessionId, newMapResourceID.GetName, MgResourceType.MapDefinition)

  82:  

  83:         'now lets deal with the layout - we need to load up the library layout, update the map definition, and save it to the repository

  84:         Dim layoutResourceID As New MgResourceIdentifier(gszLayoutResID)

  85:         Dim newLayoutResourceID As New MgResourceIdentifier("Session:" & szSessionId & "//" & layoutResourceID.GetName() & "." & MgResourceType.WebLayout)

  86:  

  87:         'same process here, load the XML, parse the XML into the new .net Object

  88:         Dim layoutXML As XmlDocument = GetResourceXML(resSvc, layoutResourceID)

  89:  

  90:         Dim newLayout As New OSGeo.MapGuide.Objects.WebLayout

  91:         newLayout = OSGeo.MapGuide.Objects.WebLayout.Parse(layoutXML.OuterXml)

  92:  

  93:         'update the map resource ID in the layout to point to our newly created map in the session

  94:         newLayout.Map.ResourceId = newMapResourceID.ToString

  95:  

  96:         'finally go through the motinos to save the layout to the session

  97:         Dim newLayoutXML As New XmlDocument

  98:         newLayoutXML.PreserveWhitespace = True

  99:         newLayoutXML.LoadXml(newLayout.Untyped.ToString())

 100:  

 101:         CreateSessionResource(resSvc, newLayoutXML, szSessionId, newLayoutResourceID.GetName, MgResourceType.WebLayout)

 102:  

 103:         'our last step is to update the src attribute of the iframe with the information needed to load the newly created layout

 104:         SetupIFrame(newLayoutResourceID, szSessionId)

 105:     End Sub

 106:     Private Sub SetupIFrame(ByVal layoutResId As MgResourceIdentifier, ByVal szSessionID As String)

 107:         'build the URL based on our constants, and the layout + session info

 108:         Dim szUrl As String = gszViewerUrl & "?WEBLAYOUT=" & layoutResId.ToString & "&SESSION=" & szSessionID

 109:  

 110:         'update the iframe

 111:         ifrmViewer.Attributes.Add("src", szUrl)

 112:     End Sub

 113:     ''' <summary>

 114:     ''' Adds a layer group to the passed MapDefinition, and returns the updated MapDefinition Object.

 115:     ''' If desired, additional parameters could be added to this to customize the various other properties

 116:     ''' like ShowInLegend etc        

 117:     ''' </summary>

 118:     ''' <param name="mapDef">The loaded MapDefinition obect</param>

 119:     ''' <param name="szLayerGroupName">The Layer Name of the new layer group</param>

 120:     ''' <param name="szLayerGroupAlias">The Layer Alias of the new layer group</param>

 121:     ''' <returns>the passed MapDefinition, with the new layer group added</returns>

 122:     ''' <remarks></remarks>

 123:     Public Shared Function AddMapLayerGroup(ByVal mapDef As OSGeo.MapGuide.Objects.MapDefinition, ByVal szLayerGroupName As String, ByVal szLayerGroupAlias As String) As OSGeo.MapGuide.Objects.MapDefinition

 124:         Dim newLayGRoup As New OSGeo.MapGuide.Objects.MapLayerGroupType

 125:         newLayGRoup.Name = szLayerGroupName

 126:         newLayGRoup.LegendLabel = szLayerGroupAlias

 127:         newLayGRoup.ShowInLegend = "True"

 128:         newLayGRoup.ExpandInLegend = "True"

 129:         newLayGRoup.Visible = "True"

 130:         newLayGRoup.Group = ""

 131:         mapDef.MapLayerGroup.Add(newLayGRoup)

 132:         Return mapDef

 133:     End Function

 134:  

 135:     ''' <summary>

 136:     ''' Adds all layer definitions within the specified repository folder to the specified map

 137:     ''' </summary>

 138:     ''' <param name="resSvc">An open resource service connection</param>

 139:     ''' <param name="newMap">the MapDefinition object to modify</param>

 140:     ''' <param name="resLocation">The folder in the repository to search for layer objects</param>

 141:     ''' <returns>Update MapDefinition object</returns>

 142:     ''' <remarks></remarks>

 143:     Public Shared Function AddFolderOfLayers(ByRef resSvc As MgResourceService, ByVal newMap As OSGeo.MapGuide.Objects.MapDefinition, ByVal resLocation As MgResourceIdentifier, ByVal szLayerGroupName As String) As OSGeo.MapGuide.Objects.MapDefinition

 144:         'get the list of layers in the folder

 145:         Dim resList As OSGeo.MapGuide.Objects.ResourceList

 146:         'use GetAllResources to get a new resList

 147:         resList = GetAllResources(resSvc, resLocation, 1, MgResourceType.LayerDefinition)

 148:  

 149:         'resList items are pretty much a collection of resrouceDocumentLocalTypes so define one of these to use in the for loop

 150:         Dim resItem As OSGeo.MapGuide.Objects.ResourceList.ResourceDocumentLocalType

 151:  

 152:         'define a new layerResID to use in the loop

 153:         Dim layerResID As MgResourceIdentifier

 154:  

 155:         'for each layer - process it and add it to the map

 156:         Dim newLayerType As New OSGeo.MapGuide.Objects.MapLayerType

 157:         For Each resItem In resList.ResourceDocument

 158:             layerResID = New MgResourceIdentifier(resItem.ResourceId)

 159:             'for adding a layer to the map - we must use the MapLayerType object 

 160:             newLayerType = New OSGeo.MapGuide.Objects.MapLayerType

 161:             newLayerType.ResourceId = layerResID.ToString

 162:             'Be sure to specify the name of the 

 163:             newLayerType.Group = szLayerGroupName

 164:             newLayerType.Name = layerResID.GetName

 165:             newLayerType.Selectable = "false"

 166:             newLayerType.ShowInLegend = "true"

 167:             newLayerType.LegendLabel = layerResID.GetName

 168:             newLayerType.ExpandInLegend = "true"

 169:             newLayerType.Visible = "true"

 170:  

 171:             newMap.MapLayer.Insert(0, newLayerType)

 172:         Next

 173:         'return the updated MapDefinition

 174:         Return newMap

 175:     End Function

 176:  

 177:     'Some handy functions

 178:  

 179:     ''' <summary>

 180:     ''' Saves the specified XMLDocument to the session respository

 181:     ''' </summary>

 182:     ''' <param name="resSvc">The open resource service connection</param>

 183:     ''' <param name="xmlDoc">the XMLDocument to save to the session repository</param>

 184:     ''' <param name="szSessionId">String containing the session ID</param>

 185:     ''' <param name="szName">The name of the newly created object in the repository</param>

 186:     ''' <param name="szResourceType">the object type</param>

 187:     ''' <returns></returns>

 188:     ''' <remarks></remarks>

 189:     Public Shared Function CreateSessionResource(ByRef resSvc As MgResourceService, ByVal xmlDoc As XmlDocument, ByVal szSessionId As String, ByVal szName As String, ByVal szResourceType As String) As MgResourceIdentifier

 190:         Dim byteSource As MgByteSource = getByteSource(xmlDoc)

 191:         Dim resID As New MgResourceIdentifier("Session:" & szSessionId & "//" & szName & "." & szResourceType)

 192:         resSvc.SetResource(resID, byteSource.GetReader, Nothing)

 193:         Return resID

 194:     End Function

 195:  

 196:     ''' <summary>

 197:     ''' Returns an MgByteSource for the passed XMLDocument

 198:     ''' </summary>

 199:     ''' <param name="xmlDoc">The XMLDocument to convert</param>

 200:     ''' <returns>MgByteSource of the XMLDocumnet</returns>

 201:     ''' <remarks></remarks>

 202:     Public Shared Function getByteSource(ByVal xmlDoc As XmlDocument) As MgByteSource

 203:         Dim xmlStream As New IO.MemoryStream

 204:         xmlDoc.Save(xmlStream)

 205:         Dim arrBytes() As Byte = xmlStream.ToArray()

 206:         Dim Enc As Encoding = Encoding.UTF8

 207:         Dim docString As String = New String(Enc.GetChars(arrBytes))

 208:         arrBytes = Nothing

 209:  

 210:         Dim arrOutput(docString.Length - 1) As Byte

 211:         Dim nByteCount As Integer = Enc.GetBytes(docString, 0, docString.Length, arrOutput, 0)

 212:  

 213:         Dim byteSource As New MgByteSource(arrOutput, arrOutput.Length)

 214:         byteSource.SetMimeType(MgMimeType.Xml)

 215:  

 216:         Return byteSource

 217:     End Function

 218:  

 219:     ''' <summary>

 220:     ''' returns a loaded XML document of the specified resourceID

 221:     ''' </summary>

 222:     ''' <param name="resSvc">An open connection to the Mapguide Resource Service</param>

 223:     ''' <param name="resId">The MgResourceID of the entity in question</param>

 224:     ''' <returns>A loaded XMLDocument of the specified resource</returns>

 225:     ''' <remarks></remarks>

 226:     Public Shared Function GetResourceXML(ByRef resSvc As MgResourceService, ByVal resId As MgResourceIdentifier) As XmlDocument

 227:         Dim retDoc As New XmlDocument

 228:         retDoc.PreserveWhitespace = True

 229:  

 230:         Dim szXML As String = resSvc.GetResourceContent(resId).ToString()

 231:         Dim nByteCount As Integer

 232:         Dim arrByte(szXML.Length) As Byte

 233:         nByteCount = Encoding.UTF8.GetBytes(szXML, 0, szXML.Length, arrByte, 0)

 234:  

 235:         Dim memStream As New IO.MemoryStream(arrByte)

 236:         retDoc.Load(memStream)

 237:         Return retDoc

 238:     End Function

 239:  

 240:  

 241:     ''' <summary>

 242:     ''' Create a new mapguide session and return the resulting session ID

 243:     ''' </summary>

 244:     ''' <param name="szMGUser">Valid mapguide user name</param>

 245:     ''' <param name="szMGPass">Valid password for the specified mapguide user name</param>

 246:     ''' <param name="szMGWebTier">The path to the Mapguide web tier (valid on the mapguide web server</param>

 247:     ''' <returns>MgSiteConnection - the newly created mapguide site connection</returns>

 248:     ''' <remarks></remarks>

 249:     Public Shared Function CreateMGSession(ByVal szMGUser As String, ByVal szMGPass As String, ByVal szMGWebTier As String) As MgSiteConnection

 250:         MapGuideApi.MgInitializeWebTier(szMGWebTier)

 251:         Dim siteConnection As New MgSiteConnection()

 252:         siteConnection.Open(New MgUserInformation(szMGUser, szMGPass))

 253:         Return siteConnection

 254:     End Function

 255:  

 256:     ''' <summary>

 257:     ''' Converts MgReader to XMLDocument

 258:     ''' </summary>

 259:     ''' <param name="byteReader">Loaded MgByteReader</param>

 260:     ''' <returns>Loaded XMLDocument</returns>

 261:     ''' <remarks></remarks>

 262:     Public Shared Function ConvertMgReaderXml(ByVal byteReader As MgByteReader) As XmlDocument

 263:         Dim szXML As String

 264:         Try

 265:             szXML = byteReader.ToString

 266:         Catch ex As Exception

 267:             Throw ex

 268:         End Try

 269:         Dim nByteCount As Integer

 270:         Dim arrByte(szXML.Length) As Byte

 271:         Try

 272:             nByteCount = Encoding.UTF8.GetBytes(szXML, 0, szXML.Length, arrByte, 0)

 273:         Catch ex As Exception

 274:             Throw ex

 275:         End Try

 276:  

 277:         Dim memStream As New IO.MemoryStream(arrByte)

 278:         Dim retDoc As New XmlDocument

 279:         retDoc.PreserveWhitespace = True

 280:         Try

 281:             retDoc.Load(memStream)

 282:         Catch ex As Exception

 283:             memStream.Close()

 284:             memStream.Dispose()

 285:             Throw ex

 286:         End Try

 287:         memStream.Close()

 288:         memStream.Dispose()

 289:         Return retDoc

 290:     End Function

 291:  

 292:     ''' <summary>

 293:     ''' Gets a ResourceList for each item in the specified repository folder.

 294:     ''' </summary>

 295:     ''' <param name="resSvc">The opened resource server connection</param>

 296:     ''' <param name="resId">The MgResourceId of the folder we want to enumerate</param>

 297:     ''' <param name="nDepth">The folder depth to enumerate.  From the Mapguide Web API Reference:

 298:     ''' (int) Recursion depth, relative to the specified resource.

 299:     '''* If the resource is a document, depth must be set to 0.

 300:     '''* If the resource is a folder:

 301:     '''      o If the depth is equal to 0, only information about the specified folder is returned.

 302:     '''      o If the depth is greater than 0, information about the folder and its descendants up to the specified depth are returned.

 303:     '''* If the depth is -1, information about the folder and all its descendants is returned.

 304:     ''' </param>

 305:     ''' <param name="szType">Again from the Mapguide Web API Reference:

 306:     '''     (String/string) Type of the resource to be enumerated. (Case sensitive.) See MgResourceType  for valid types. If the type is a folder, 

 307:     '''     you must include the trailing slash.

 308:     '''     Or, this can be set to null, in which case information about all resource types is returned

 309:     ''' </param>

 310:     ''' <returns>OSGeo.Mapguide.Objects.ResourceList of resource entities</returns>

 311:     ''' <remarks></remarks>

 312:     Public Shared Function GetAllResources(ByRef resSvc As MgResourceService, ByVal resId As MgResourceIdentifier, ByVal nDepth As Integer, ByVal szType As String) As OSGeo.MapGuide.Objects.ResourceList

 313:         Dim retDoc As XmlDocument

 314:         retDoc = ConvertMgReaderXml(resSvc.EnumerateResources(resId, nDepth, szType))

 315:  

 316:         Dim resourceList As New OSGeo.MapGuide.Objects.ResourceList

 317:         resourceList = OSGeo.MapGuide.Objects.ResourceList.Parse(retDoc.OuterXml)

 318:         Return resourceList

 319:     End Function

 320: End Class

If you have any questions or comments – feel free to let me know.

One of my first tasks with Mapguide was to add some layers to the map, before the viewer had loaded up, save that map in the session repository and then build a layout for the map – again in the session repository.  I tried various ways of working with the XML provided by the resource  service, and read through many of the e-mails on the topic from the Osgeo list, but I just couldn’t get it to work.  So I set out on my mission to get an object based method of getting things done.  First, as per the developer documentation I tried out xsd.exe.  XSD allowed me to get a class skeleton created, but there was a lot of work needed to a rounded API running.   I had been recently investigating the new functionality Microsoft was exposing with LINQ – and I came across LINQ to XSD.  For more information on Linq to XSD the Microsoft XML team blog is a good place to start. 

So download LINQ to XSD Alpha 0.2 and install it.  You will need to have .NET 3.5 installed first.  In addition to that I’m using Visual Studio 2008 Pro.  I have tried these steps with both Mapguide Enterprise 2008 and  2009.  I have to assume the resulting code will work with Mapguide Open Source as well.

Setting up your project

At this point you should be able to fire up Visual Studio and create a new project.  If you are a VB developer, I’m afraid you’re going to have to dive into a bit of C#, as its the only support language right now.  It’s not that bad.

The new project window should look a little like this:

Choose LINQ to XSD Library and give the project a name.  Once the new project is loaded, create a new folder called XSD.  Browse to your Mapguide 2009/OS 2.0 server Schema folder (on a default installation its c:\Program Files\Autodesk\MapGuideEnterprise2009\Server\Schema).  Take a these files and drag them into the new XSD folder.

Back in Visual Studio, select all of the XSD files.  Look in the property window and change the "Build Action" to be "LinqToXsdSchema".

Building the project

At this point, right click on the project in Visual Studio, and choose build.  You should have 173 errors.  This is caused by having multiple, similar versions of some of the XSDs.  Let’s exclude the following files:

• FdoProviderCapabilities-1.0.0.xsd
• LayerDefinition-1.0.0.xsd
• LayerDefinition-1.1.0.xsd
• LoadProcedure-1.0.0.xsd
• SymbolDefinition-1.0.0.xsd

Rebuild the project and we should be down to five errors.  I have found that by excluding the following files I was able to get the code to generate:

• ApplicationDefinition-1.0.0.xsd
• ApplicationDefinitionInfo-1.0.0.xsd
• SymbolLibrary-1.0.0.xsd

For my purposes, I was not too concerned about being able to work with these entity types programmatically (at least at this time).  If anyone is able to work around and would like to share it, please let me know.

Build the project again, and we will see three new errors.  This time we will need to dig into the generated code to correct them.  For each of the three errors we will want to change the public string name.  For example:

   1: public string DataType {

We would change to:

   1: public string Datatype {

Change the case of the property name in each of the three errors and we are just about there.  At this point you should have around 42904 lines of code in this file.  Good thing I didn’t try to do this manually.   Take a copy of all these wonderful lines o’ code, and we’re going to paste them into a new class. For the sake of this example, I renamed class1.cs to be OSGeo.Mapguide.Objects.cs and pasted the code in there.  I also wrapped all the code in a namespace to match the file name.

If you need to find the generated code, take a look in the obj folder within your project.  You should find a file named LinqToXsdSource.cs in the appropriate build folder.

Next we need to prevent the XSDs from rebuilding each time.  Select all of your XSD files again, and change the "Build Action" to "None".    Building the project at this point will generate fifty some odd errors.  We can eliminate these by doing a search and replace on global:: and replacing it with an empty string.  Build the project again, and you will find one error.  Simply remove the "global." from the line in question and the project will now build.

At this point, you should have a nice .dll file which you can reference from your projects and access many of the Mapguide entity types using objects.  Be sure to grab a copy of Microsoft.XmlSchema.Linq.dll and distribute that with your new DLL.

This project maybe have some issues.  I have worked with LayerDefinitions, MapDefinitions, and WebLayouts – but not tested many of the classes here yet.  If you have any feedback or enhancements you want to share – please let me know!

In the next week I will post some examples on how to build maps and layouts – before the viewer has loaded.

I saved a copy of the dynamically generated maps and layers to the library repository.  Everything checked out.  The layers were marked as selectable.

Next step was to check out the server logs on my Mapguide server.    We have a nice error occurring a lot: Error: An exception occurred in FDO component. String does not represent a valid filter.

So into the code I go.  I ripped out all my dynamic authoring calls, and the map loads and selects no problem.  As I was starting to suspect, my code was to blame – and there is something specific to my filters on the layers:

   1: newLayer.VectorLayerDefinition.Filter = "BLDG_ID = """ & szBldgID & """ AND BLDG_FLOOR "" IN(0," & nFloorNumber.ToString & ")"""

I had assumed that FDO had an IN clause, did a quick check in Mapguide Studio’s condition builder and didn’t see one.  Fair enough, in this case I can get by with two equals conditions in my select as the list of conditions will only ever consist of two values.

   1: newLayer.VectorLayerDefinition.Filter = "BLDG_ID = " & szBldgID & " AND (BLDG_FLOOR = 0 OR BLDG_FLOOR = " & nFloorNumber.ToString & ")"

   2: 'newLayer.VectorLayerDefinition.Filter = "BLDG_ID = " & szBldgID & " AND BLDG_FLOOR  IN(0," & nFloorNumber.ToString & ")"""

Long story short, if you are selecting items in the map viewer that are supposed to be selectable, check your server logs.

I found this problem when trying to programmatically retrieve a feature set of  the current selection.  When the SetFilter method on the MgFeatureQueryOptions call was issued I was receiving a  "Not Implemented" error.  After a bit of back and forth with Steve Dang at Autodesk he gave me a list of valid  database property types for the SetFilter call:

   1: //The problem is from the web tier.  Note that the  MgSelectionBase::GenerateFilter method

   2: //will throw an  MgNotImplementedException if the property type of the filtered data

   3: //is not one of the following types: 

   4:  

   5: MgPropertyType::Int16

   6: MgPropertyType::Int32

   7: MgPropertyType::Int64

   8: MgPropertyType::String

   9: MgPropertyType::Single

  10: MgPropertyType::Double

This got me looking at my underlying fields, and eventually I noticed in the ODBC data connection the key fields for the table in question contained a  number of columns that just should not have been there.  The problem field was a date column – which would explain why the SetFilter call was throwing and error.  Upon closer inspection I realized that these columns were constrained with "Not Null" constraints. 

So I changed my source database and removed the not null constraints.  Went back to studio to refresh the table – but the columns were still there.  Long story short – there is possibly another defect somewhere in Mapguide around data connections.  They seem to not fully update when you make changes to them.  However, creating a new data connection and pointing to the same SQL server database now shows keys without the null columns.

Moving forward in my code now generated the selection filter and things were good.

I proposed to Autodesk that they auto populate the key fields but then allow the user to modify this list, in addition to correcting the not null constraint issue.   It seems as though all primary and foreign keys are being found for the table/view and added to the list.  Fair enough, however in the view I was working with I had something like 10+ keys (due to the joins of data tables, as well as the needed lookup tables).   In reality – I only was interested in one of those fields.  Filtering based on that one field was enough to uniquely identify the data in question.  I’m not really familiar with the way FDO does things so this might not be possible.