Opening a WinForms Form with TopMost = true but not having it steal focus?

Question

I have a form that pops up on a user's screen and has TopMost=true, but it steals the focus. How can I get it to not steal focus when it first appears?

Answer 1

This is what worked for me. It provides TopMost but without focus-stealing.

    protected override bool ShowWithoutActivation
    {
       get { return true; }
    }

    private const int WS_EX_TOPMOST = 0x00000008;
    protected override CreateParams CreateParams
    {
       get
       {
          CreateParams createParams = base.CreateParams;
          createParams.ExStyle |= WS_EX_TOPMOST;
          return createParams;
       }
    }

Remember to omit setting TopMost in Visual Studio designer, or elsewhere.

This is stolen, err, borrowed, from here (click on Workarounds):

https://connect.microsoft.com/VisualStudio/feedback/details/401311/showwithoutactivation-is-not-supported-with-topmost

Answer 2

Paste this code in your form:

protected override bool ShowWithoutActivation
{
    get { return true; }
}