Why do my toolbox items disappear in Visual Studio

问题:

I'm working on a solution that contains multiple projects targeting Windows Mobile 5 and standard Windows applications.

Lately when opening up a form in designer the common UI controls (textbox, button, label, etc etc...) have vanished leaving only the controls defined within the project.

Resetting the toolbox has no effect. A google search suggested deleting the toolbox temp files in the Local Settings\Application Data\Microsoft\VisualStudio\9.0, however this was only successful in bringing back the default controls for Windows Mobile 5. The WinForms controls are still mysteriously missing.

Also, if I right-click and Select All on the toolbox, all of the WinForms controls do in fact come up, however they're all grayed out.

Has anyone else experienced this?

回答1:

I just had a similiar problem. In a managed C++ project all the default toolbox items disappeared form the winforms designer. After playing around for a while I found that there was a problem in the .vcproj file.

<VisualStudioProject
    ProjectType="Visual C++"
    Version="9,00"
    Name="COLLADA Import"
    ProjectGUID="{0DEEF9B6-1929-44E3-92EC-13712839FB63}"
    RootNamespace="COLLADAImport"
    Keyword="ManagedCProj"
    TargetFrameworkVersion="0"
    >

When you set TargetFrameworkVersion to a valid number, for example 131072 for .Net 2.0, the toolbox items will be back.

回答2:

If you right click on the Toolbox and select 'Choose Items...' and then sort by the 'Namespace' column, you can then select the ones you need (for example System.Windows.Forms for WinForms).

You can multiselect with Shift and then select/deselect the group.

The controls then reappear in the Toolbox as enabled.

回答3:

I've noticed this exact same thing for regular WinForms as well. I can't speak to mobile applications but in regular winforms this has a tendency to happen.

I believe it's actually a bug in Visual Studio.

There are some things you can do (again, for WinForms. I'm not sure about mobile) with adding attributes to your control. Such as:

[ToolboxBitmap(typeof(MyControl), "MyControlBitmap")]

There are some other useful related things on this site:

http://en.csharp-online.net/Design-Time_Integration-Attributes

回答4:

I had exactly the same problem (after installing Windows Mobile SDK all items in the toolbox were greyed out).

I've startet the Visual Studio 2008 command line as administrator and started the following command (WARNING - all your settings are lost !!)

devenv /setup /resetuserdata /selfreg /resetskippkgs

After that the toolbox looked fine and worked like on the first day. The idea came from this thread: connect.microsoft.com

回答5:

Go to the Tools menu and choose import & export settings, then choose the 'reset all' setting, then yes. Save your current settings, after that you'll have your toolbox reappear.

回答6:

Actually you may be able to add a registry key to get this to work also.

回答7:

Make sure you're not in Debug mode.

回答8:

If you are running Visual Studio 2008 under vista, try running it as an Administrator. Right click on the shortcut and select Run as Administrator.

回答9:

Well guess what install Service pack 1 for VS 2008 and it would go away and if you have wireless mouse and keyboard turn it off. Choose one of these two both work.