C# Signature:

[DllImport("user32.dll")]
static extern bool GetWindowRect(IntPtr hWnd, out RECT lpRect);

User-Defined Types:

RECT

Notes:

The Win32 RECT is not binary compatible with System.Drawing.Rectangle.

Tips & Tricks:

Please add some!

Sample Code:

        [DllImport("user32.dll")]
        static extern bool GetWindowRect(IntPtr hWnd, out RECT lpRect);

        [Serializable, StructLayout(LayoutKind.Sequential)]
        public struct RECT
        {   public int Left;    
            public int Top;    
            public int Right;    
            public int Bottom;
        }

        private void button1_Click(object sender, System.EventArgs e)
        {
            RECT msnWindow=new RECT();

            IntPtr hWn=new IntPtr(00263614);

            if(!GetWindowRect(hWn, out msnWindow))
            {
                MessageBox.Show("ERROR");
            }

        }

Alternative Managed API:

Do you know one? Please contribute it!