Running a DOS command

Occasionally you might find that you want to run a dos command from your VB program. The easiest way to do this is create a batch file (*.bat) containing the command (ie registering a number of components). Your program can then call this file, and wait until it has finished using the code below

Private Sub cmdDos_Click()
    Dim lngTask As Long, lRet As Long, pHandle As Long
    '// start the dos program
    lngTask = Shell(App.Path & "pointless.bat", vbMinimizedNoFocus)
    '// get a handle on the window
    pHandle = OpenProcess(SYNCHRONIZE, False, lngTask)
    lblStatus.Caption = "Running DOS program..."
    lblStatus.Refresh
    cmdDOS.Enabled = False
    Do
        '// you can pass INFINITE instead of 0 if you wish, and your
        '// program will 'hang' here until the program is finished
        lRet = WaitForSingleObject(pHandle, 0)
        DoEvents
    Loop While lRet <> 0
    lblStatus.Caption = "Finished"
    
    lRet = CloseHandle(pHandle)  'Close the task
    cmdDOS.Enabled = True
End Sub

Private Sub Form_Unload(Cancel As Integer)
    If cmdNotepad.Caption = "Close Notepad" Then Call cmdNotepad_Click
End Sub