How to automate response to msgbox

Question

I am developing a C# application to automate the running of a legacy VBScript(vbs) file which calls several VB6 .exe files. The .exe files have message box pop-ups that I need t

Answer 1

You can do this in C# without needing some external utility. The trick is to search for the message box dialog and click its OK button. Doing it more than once requires a Timer that keeps searching for such a dialog and clicking it away. Add a new class to your project and paste this code:

using System;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;

class MessageBoxClicker : IDisposable {
  private Timer mTimer;

  public MessageBoxClicker() {
    mTimer = new Timer();
    mTimer.Interval = 50;
    mTimer.Enabled = true;
    mTimer.Tick += new EventHandler(findDialog);
  }

  private void findDialog(object sender, EventArgs e) {
    // Enumerate windows to find the message box
    EnumThreadWndProc callback = new EnumThreadWndProc(checkWindow);
    EnumThreadWindows(GetCurrentThreadId(), callback, IntPtr.Zero);
    GC.KeepAlive(callback);
  }

  private bool checkWindow(IntPtr hWnd, IntPtr lp) {
    // Checks if  is a dialog
    StringBuilder sb = new StringBuilder(260);
    GetClassName(hWnd, sb, sb.Capacity);
    if (sb.ToString() != "#32770") return true;
    // Got it, send the BN_CLICKED message for the OK button
    SendMessage(hWnd, WM_COMMAND, (IntPtr)IDC_OK, IntPtr.Zero);
    // Done
    return false;
  }

  public void Dispose() {
    mTimer.Enabled = false;
  }

  // P/Invoke declarations
  private const int WM_COMMAND = 0x111;
  private const int IDC_OK = 2;
  private delegate bool EnumThreadWndProc(IntPtr hWnd, IntPtr lp);
  [DllImport("user32.dll")]
  private static extern bool EnumThreadWindows(int tid, EnumThreadWndProc callback, IntPtr lp);
  [DllImport("kernel32.dll")]
  private static extern int GetCurrentThreadId();
  [DllImport("user32.dll")]
  private static extern int GetClassName(IntPtr hWnd, StringBuilder buffer, int buflen);
  [DllImport("user32.dll")]
  private static extern IntPtr GetDlgItem(IntPtr hWnd, int item);
  [DllImport("user32.dll")]
  private static extern IntPtr SendMessage(IntPtr hWnd, int msg, IntPtr wp, IntPtr lp);
}

Sample usage:

private void button1_Click(object sender, EventArgs e) {
  using (new MessageBoxClicker()) {
    MessageBox.Show("gonzo");
  }
}