Getting the position of a windows application from C#

Question

I need some help with trying to get the position of the notepad window. I'm pretty sure I need to use the GetWindowRect function, which is below, but I do not know how to use it. I've put what is below in to a win form project, but myRect.X, myRect.Y, etc. did not have anything in them. I though they should've at least had the x, y, width, height, of the winform I was working in. But it always displayed 0. honestly I just don't understand how to use this. Ive looked around for a 5ish hours now. but haven't learned anything.

[DllImport("user32.dll")]
     [return: MarshalAs(UnmanagedType.Bool)]
     static extern bool GetWindowRect(HandleRef hWnd, out RECT lpRect);

     [StructLayout(LayoutKind.Sequential)]
     public struct RECT
     {
         public int Left;        // x position of upper-left corner
         public int Top;         // y position of upper-left corner
         public int Right;       // x position of lower-right corner
         public int Bottom;      // y position of lower-right corner
     }

     Rectangle myRect = new Rectangle();

     private void button1_Click(object sender, System.EventArgs e)
     {
         RECT rct;

         if(!GetWindowRect(new HandleRef(this, this.Handle), out rct ))
         {
             MessageBox.Show("ERROR");
             return;
         }
         MessageBox.Show( rct.ToString() );

         myRect.X = rct.Left;
         myRect.Y = rct.Top;
         myRect.Width = rct.Right - rct.Left + 1;
         myRect.Height = rct.Bottom - rct.Top + 1;
     }

I’ve also tried the code below, but still the most I got out of this is DrawingBasicShapes.Form1+Rect located in the NotepadRect.

Then there is true in the GetWindowRect(ptr, ref NotepadRect). I used MessageBox.Show(Convert.ToString(NotepadRect)); to get what was inside.. Same for the other, I’m thinking that was wrong. But I do not know how to show what’s in it.

I was expecting numbers or something to be in here but I guess not. I’m sorry if this is a novice question, or if the answer is clear to you. But I normally do not work with dll import. So I am slowly learning how to use it...

[DllImport("user32.dll", CharSet = CharSet.Auto)]
public static extern IntPtr FindWindow(string strClassName, string strWindowName);

[DllImport("user32.dll")]
public static extern bool GetWindowRect(IntPtr hwnd, ref Rect rectangle);

public struct Rect
{
  public int Left { get; set; }
  public int Top { get; set; }
  public int Right { get; set; }
  public int Bottom { get; set; }
}

Process[] processes = Process.GetProcessesByName("notepad");
Process lol = processes[0];
IntPtr ptr = lol.MainWindowHandle;
Rect NotepadRect = new Rect();
GetWindowRect(ptr, ref NotepadRect);

Answer 1

If all you are putting in your messagebox is the Rect object itself, that's exactly what output you're going to get.

Output your messagebox as follows:

MessageBox.Show( string.Format("Left: {0}\r\nTop: {1}\r\nRight: {2}\r\nBottom: {3}", NotepadRect.Left, NotepadRect.Top, NotepadRect.Right, NotepadRect.Bottom));

Answer 2

The Rect struct does not override ToString. Therefore converting it to string will only yield the full type name. Nothing else.

Try

string s = String.Format("left = {0}, top = {1}, right = {2}, bottom = {3}",
    NotepadRect.Left, NotepadRect.Top, NotepadRect.Right, NotepadRect.Bottom);
MessageBox.Show(s);

Alternatively you could override ToString in Rect:

public struct Rect
{
    public int Left { get; set; }
    public int Top { get; set; }
    public int Right { get; set; }
    public int Bottom { get; set; }

    public override string ToString()
    {
        return String.Format("left = {0}, top = {1}, right = {2}, bottom = {3}",
            Left, Top, Right, Bottom);
    }
}

Then MessageBox.Show(NotepadRect) will work as expected.