How to block double click in overridden WndProc function in Windows Forms?

Question

I have a form created in Windows Forms which is draggable wherever I click. I made it by overriding WndProc function which in turn modifies each click as it was a title bar

Answer 1

It seems you found a solution to a problem with caused another problem that you're trying to solve. If I could suggest something simple, just a better solution to make a window drag-able:

Add InteropServices to the using declarations:

using System.Runtime.InteropServices;

And for the code:

    public const int WM_NCLBUTTONDOWN = 0xA1;
    public const int HT_CAPTION = 0x2;

    [DllImportAttribute("user32.dll")]
    public static extern int SendMessage(IntPtr hWnd,
                     int Msg, int wParam, int lParam);
    [DllImportAttribute("user32.dll")]
    public static extern bool ReleaseCapture();

Then go to the form's MouseDown event and paste this:

        if (e.Button == MouseButtons.Left)
        {
            ReleaseCapture();
            SendMessage(Handle, WM_NCLBUTTONDOWN, HT_CAPTION, 0);
        }

Done.