Home/ Questions/Q 4620026
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-05-22T02:30:15+00:00

In VS2010 I had a project targeting .NET Framework 4.0 and then had to

  • 0

In VS2010 I had a project targeting .NET Framework 4.0 and then had to revert to target v. 3.5. Once this happened, the SplitContainer object that I had will not display and will actually throw an error: “Unable to cast object of type ‘System.Windows.Forms.SplitContainer’ to type ‘System.ComponentModel.ISupportInitialize’.”

Now, I did some digging and found out that 3.5 does not, in fact, have ISupportInitialize on the SplitContainer and it does in .NET 4.0. I guess my question is, if I am targeting 3.5 and still getting this issue, how do i correct this?

Steps to reproduce problem:

  1. Create a new C# Windows Forms Application project in Visual Studio 2010 (Make sure to target .NET Framework 4.0)
  2. Add a split container to the basic form.
  3. Run the application (will run just fine)
  4. Change target to .NET Framework 3.5 (properties->Applications->Target Framework:)
  5. Rerun the application (It will crash with the Cast exception).

Any help with this would be greatly appreciated!

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    I found the solution to this problem and it was quite special… IF you backrev your forms to 3.5, you have to do a small change on EACH AND EVERY form you have in your program so that the compiler will regenerate all of the code for that form. The reason I was having an issue was because I had made no change and was trying to run the code, which had not been regenerated.

    • 0