FormStartPosition.CenterParent does not work

Question

In the following code, only the second method works for me (.NET 4.0). FormStartPosition.CenterParent does not center the child form over its parent. Why?

Answer 1

I had the same problem, I eventually went with this:

protected override void OnActivated(EventArgs e) {
    if(this.Modal == false && this.StartPosition == FormStartPosition.CenterParent) {
        if(!(this.Owner is Form)) {
            // Center to the last form opened before this one
            int numforms = Application.OpenForms.Count;
            this.Owner = Application.OpenForms[numforms - 2];
        }
        this.CenterToParent();
        Application.DoEvents();
    }
    base.OnActivated(e);
}

Used as:

MyForm form = new MyForm();
form.Show(this); // with or without

The main advantage is that it does what your colleagues expect it to do, without requiring any hack in the calling form.