Hi Everyone:

I sure hope someone can help. The environment is Vista Enterprise (UAC turned off), Microsoft Visual Studio 2008 (Release, NOT orcas beta 2), Microsoft Mappoint 2006, C# language.

If I create a new windows form application, add the Mappoint COM object to the toolbox (Mappoint control 13.0), then drop it on the form, then try to run it... she fails with..

"InvalidOperationException" Cross-Thread operation not valid: Control 'axMappointControl1' accessed from a thread other than the thread it was created on.

This is like the 'hello world' of putting a mappoint object onto a form. The problem started with Orcas Beta 2 and has not gone away for myself or any of our developers. The result is our application, which used mappoint since 2004, can no longer bring up a mappoint map at all because of this failure.

For grins, I have attached this ultra simple mappoint test. Mappoint 2006 is loaded on the machine and does come up if I run it manually (As a separate program), but I can't get it to come up on a windows form at all, from anything (wheras, we had no trouble with VS 2005).

Anybody else run into this strange and bizzare interaction for the COM object in VS 2008? Any suggestions are appreciated. Thanks

Jovo

I haven't played with VS2008 & C#, but I know that Microsoft have been busy adding multi-threading tools to the latest versions of .NET and C#. Could it be that there's a default setting changed for the form, so that it is doing what the error says? Ie. different threads are being used to create and access control?

Some of the new multi-threading stuff looks pretty neat - eg. a foreach that works a bit like the old vector processing operatives seen on Crays, Convexes, etc. Shame it will be a few years before a substantial number of PCs have it installed as standard...


Richard

Hi,

Are you very sure you don't access any of the mappoint things from in another thread as the one where the form is created ?

Hi Wilfried -

I appreciate your asking, but that is why I posted the project. The project posted is simply, create a new windows form, drop the mappoint control on the form and try to run the program. On VS 2008 (release) running framework 3.5 (release) on MS vista (32 bit, enterprise edition -- any edition fails), the cross-threading error comes up.

There is no additional coding in place. Please try the project on a vista machine with vs 2008 and mappoint. If it somehow works for you where it has failed on all 20 of our vista test environments and development machines, then I would very much like to know how to get it to work on vista.

The same project, compiled.. may run on Win XP. In particular, if I use AxInterop.Mappoint.dll generated by VS 2005 (the older vs) on an XP machine, then mappoint comes up fine on an XP machine. But not vista... the cross-threading error happens.

Hi,

I have no Vista machine here, and still not installed VS2008. But you could try if it is indeed running in same thread using GetCurrentThreadId (which has been deprecated) or ManagedThreadId because then you can determine if it is a bug in vista or in VS2008.

Hi
Has anybody found a solution for this issue sofar?
LG
Daniel

Hi, I just tried this for you in VS2008 and get the same error message as you. I googled for the error and found this which may be useful.

http://www.microsoft.com/communities...&cr=&sloc=&p=1

I've not tried the suggestions in VS2008 as I use still use 2005 and it sounds like the workaround may work for some and not others.

John.

Jovo. I hope you found a solution to your problem if not this may help.

I was having the same prolblem and it is due to the DEP security level this is a solution that I warranty has worked for me.


You can work around the issue by manipulating the control at run time. For Example - I was able to position the control at runtime using the following line of code:

AxMappointControl1.Location = New System.Drawing.Point(100, 100)
AxMappointControl1.Size = New System.Drawing.Size(New Drawing.Point(800, 600))

When we run the project it throws the exception “Map point failed to load. The cause of this failure is unknown”, I was able to resolve the above error by following below steps :-

1) Go to “Project->Properties” then select the “Compile” tab. In the “Compile” tab click the “Build Events…” button.
2) In the “Post-build event command line” text-Area copy the following lines:
call "$(DevEnvDir)..\tools\vsvars32.bat"
editbin.exe /NXCOMPAT:NO "$(TargetPath)"
3) Save the project, build it & try to run the project.

If you still get the exception while running the project try the following:
1) Do not remove the lines we entered in the post-Build event (in step 2 above)
2) Press Ctrl+F5 to see if the application runs well without debugging.
3) Open the project's Property page, and go to "Debug" tab. UNCHECK the "Enable the Visual Studio hosting process"
4) Press F5 to see if the application runs well under debugging now.

hi.frnd am working with Visula studio 2008..my requirement is that i want to make a Windows mobile pocket pc applicatio...by which i can add map facilities.i have that map control dll..but when i add it in tool box ..the controls are not comming..plz tell me what to do?

Hi.

I dont hav much experience with windows mobile, but could you explain the following a little more?

1 What mobile OS are you trageting?

2 When you say "when i add it in tool box ..the controls are not comming" can you explain dose the Mappoint control not show up in the tool box or dose it not show up on your form??

3 What have you installed in your machine a full version of mappoint or the redisitribuable?

4 are you trying to add the mappoint control or the streetmap control??

brgds
JB