How To Copy the Screen or Active Window to the Clipboard from Visual Basic (240653)

MORE INFORMATION

The code included in Knowledge Base article: shows how to capture any form or window, including the screen, and place it in a Visual Basic Picture object. If the only requirement is to copy the active window or screen to the clipboard, the keybd_event API is a much easier and lower overhead approach. Calling the keybd_event API achieves the same functionality as entering the key combinations PRINTSCRN (copy the screen to the clipboard) or ALT+PRINTSCRN (copy the active window to the clipboard). If you also need to print the image, a hidden PictureBox can provide this functionality.

Step-by-step Example

1. Start a new Visual Basic Standard EXE project. Form1 is created by default.
2. Add three CommandButtons and a PictureBox to Form1.
3. Add the following code into the General Declarations section of Form1:

   Option Explicit
   
   Private Declare Sub keybd_event Lib "user32" (ByVal bVk As Byte, ByVal _
      bScan As Byte, ByVal dwFlags As Long, ByVal dwExtraInfo As Long)
   
   Private Declare Function GetVersionExA Lib "kernel32" _
         (lpVersionInformation As OSVERSIONINFO) As Integer
   
   Private Type OSVERSIONINFO
       dwOSVersionInfoSize As Long
       dwMajorVersion As Long
       dwMinorVersion As Long
       dwBuildNumber As Long
       dwPlatformId As Long
       szCSDVersion As String * 128
   End Type
   
   Private Const KEYEVENTF_KEYUP = &H2
   Private Const VK_SNAPSHOT = &H2C
   Private Const VK_MENU = &H12
   
   Dim blnAboveVer4 As Boolean
   
   Private Sub Command1_Click()
       If blnAboveVer4 Then
           keybd_event VK_SNAPSHOT, 0, 0, 0
       Else
           keybd_event VK_SNAPSHOT, 1, 0, 0
       End If
   End Sub
   
   Private Sub Command2_Click()
       If blnAboveVer4 Then
           keybd_event VK_SNAPSHOT, 1, 0, 0
       Else
           keybd_event VK_MENU, 0, 0, 0
           keybd_event VK_SNAPSHOT, 0, 0, 0
           keybd_event VK_SNAPSHOT, 0, KEYEVENTF_KEYUP, 0
           keybd_event VK_MENU, 0, KEYEVENTF_KEYUP, 0
       End If
   End Sub
   
   Private Sub Command3_Click()
       ' Load the captured image into a PictureBox and print it
       Picture1.Picture = Clipboard.GetData()
       Printer.PaintPicture Picture1.Picture, 0, 0
       Printer.EndDoc
   End Sub
   
   Private Sub Form_Load()
       Dim osinfo As OSVERSIONINFO
       Dim retvalue As Integer
      
       osinfo.dwOSVersionInfoSize = 148
       osinfo.szCSDVersion = Space$(128)
       retvalue = GetVersionExA(osinfo)
       If osinfo.dwMajorVersion > 4 Then blnAboveVer4 = True
   
       Picture1.Visible = False
       Command1.Caption = "Print Screen"
       Command2.Caption = "Alt+Print Screen"
       Command3.Caption = "Print Image"
   End Sub
   					

4. Open Microsoft Paint, and then run the project.
5. Click the Print Screen button, switch to Paint, and press CTRL+V to paste the contents of the clipboard into Paint. The entire screen is pasted.
6. Click the Alt+Print Screen button, switch to Paint as before, and press CTRL+V again. Only the active window is pasted.
7. Click the Print Image button and the captured image will print (using a hidden PictureBox).