Perform a mouse Click event on another Application using C#

Question

what i need to do is that I need to control another application installed on the same machine using my custom application. For example if i needed to use the standard window

Answer 1

Maybe this could help you

Code

The task

• Getting the mouse's current position
• Sending the mouse event

Windows forms

...
using System.Runtime.InteropServices;

namespace yournamespace
{

 public partial class yourclassname
 {
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
    public static extern void mouse_event(uint dwFlags, uint dx, uint dy, uint cButtons, uint dwExtraInfo);

    private const int MOUSEEVENTF_LEFTDOWN = 0x02;
    private const int MOUSEEVENTF_LEFTUP = 0x04;
    private const int MOUSEEVENTF_RIGHTDOWN = 0x08;
    private const int MOUSEEVENTF_RIGHTUP = 0x10;

    int X = Cursor.Position.X;
    int Y = Cursor.Position.Y;
    mouse_event(MOUSEEVENTF_LEFTDOWN | MOUSEEVENTF_LEFTUP, X, Y, 0, 0);
  }
}   

WPF

Things are a bit harder in WPF

double mousePointX;
double mousePointY;
[DllImport("user32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool GetCursorPos(out POINT lpPoint);

[StructLayout(LayoutKind.Sequential)]
public struct POINT
{
  public int X;
  public int Y;

  public POINT(int x, int y)
  {
      this.X = x;
      this.Y = y;
  }
}

private void WritePoint(object sender, RoutedEventArgs e)
{
    POINT p;
    if (GetCursorPos(out p))
    {
        System.Console.WriteLine(Convert.ToString(p.X) + ";" + Convert.ToString(p.Y));
    }
}
[DllImport("User32.dll")]
static extern IntPtr GetDC(IntPtr hwnd);

[DllImport("gdi32.dll")]
static extern int GetDeviceCaps(IntPtr hdc, int nIndex);

[DllImport("user32.dll")]
static extern bool ReleaseDC(IntPtr hWnd, IntPtr hDC);

private Point ConvertPixelsToUnits(int x, int y)
{
    // get the system DPI
    IntPtr dDC = GetDC(IntPtr.Zero); // Get desktop DC
    int dpi = GetDeviceCaps(dDC, 88);
    bool rv = ReleaseDC(IntPtr.Zero, dDC);

    // WPF's physical unit size is calculated by taking the 
    // "Device-Independant Unit Size" (always 1/96)
    // and scaling it by the system DPI
    double physicalUnitSize = (1d / 96d) * (double)dpi;
    Point wpfUnits = new Point(physicalUnitSize * (double)x,
    physicalUnitSize * (double)y);

    return wpfUnits;          
}
private void WriteMouseCoordinatesInWPFUnits()
{
    POINT p;
    if (GetCursorPos(out p))
    {
    Point wpfPoint = ConvertPixelsToUnits(p.X, p.Y);
    System.Console.WriteLine(Convert.ToString(wpfPoint.X) + ";" +   Convert.ToString(wpfPoint.Y));

    mousePointY = wpfPoint.Y;
    mousePointX = wpfPoint.X
    }
}

Now the most important part of the code

 [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
    public static extern void mouse_event(uint dwFlags, uint dx, uint dy, uint cButtons, uint dwExtraInfo);

    private const int MOUSEEVENTF_LEFTDOWN = 0x02;
    private const int MOUSEEVENTF_LEFTUP = 0x04;
    private const int MOUSEEVENTF_RIGHTDOWN = 0x08;
    private const int MOUSEEVENTF_RIGHTUP = 0x10;

    ...    
        mouse_event(MOUSEEVENTF_LEFTDOWN | MOUSEEVENTF_LEFTUP,   Convert.ToUInt32(mousePointX), Convert.ToUInt32(mousePointY), 0, 0); 
    ...

Warning

• The code is tested
• The code is not a "copy & paste code