Cannot Place User Control on Form

Question

I\'ve created a C# WinForms application using VS2010. I\'m new to creating user controls so I created a new user control (as part of the same project).

When I rebuil

Answer 1

My application need to be 64-bit. In order to use custom user controls in the designer I just added a new project to my solution. This new project use the "AnyCPU" setting and contains all my user controls.

My solution contains the following projects:

• MyApp which is my main project (Windows Form Application) compiled in 64-bit and referencing my second project
• MyApp.UI.UserControls (class library) is compiled for "Any CPU" and contains all my user controls

Works like a charm and it's clean

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By the way, there is a Microsoft support article about that issue.

• Action: You attempt to use a 64-bit component within the Microsoft Visual Studio Integrated Development Environment (IDE).
• Error cause: This behavior is by design. Visual Studio is a 32-bit process, and therefore can only execute 32-bit modules. While Visual Studio allows you to add a reference to a 64-bit assembly, it cannot actually JIT compile it to 64-bit and execute it in process.
• Resolution:
  1. Rebuild the assembly using the "AnyCPU" setting. This would allow the component to run within a 32-bit process (such as Visual Studio), or in a 64-bit process.
  2. Add the assembly as a reference and load the control dynamically at run-time. Although you still would be unable to use the control within any designer inside Visual Studio, you can still write the code needed to instantiate the control and set it's properties accordingly.

Source: http://support.microsoft.com/kb/963017