Q242018: HOWTO: Copy a Section of a Bitmap to the Clipboard

Article: Q242018
Product(s): Microsoft Visual Basic for Windows
Version(s): WINDOWS:5.0,6.0
Operating System(s): 
Keyword(s): kbBitmap kbClipboard kbCtrl kbVBp kbVBp500 kbVBp600 kbGrpDSVB kbDSupport
Last Modified: 11-JAN-2001

-------------------------------------------------------------------------------
The information in this article applies to:

- Microsoft Visual Basic Professional Edition for Windows, versions 5.0, 6.0 
- Microsoft Visual Basic Enterprise Edition for Windows, versions 5.0, 6.0 
-------------------------------------------------------------------------------

SUMMARY
=======

This article shows how to select a region of a bitmap from a picture box and
then copy only the selected region to the clipboard. This article assumes that
you select from the top-left to the bottom-right with the mouse.

MORE INFORMATION
================

Step by Step Example
--------------------

1. Start a new Visual Basic Standard Exe project. Form1 is created by default.

2. On the Project menu, select Add Module to add a new module to the existing
  project.

3. Add two Picture Boxes to the form, name one "Pic_Edit" (without the quotation
  marks) (the target), and name the other "Pic_Dest" (without the quotation
  marks) (the destination.)

4. Set the Picture property of Pic_Edit to a bitmap from which you want to
  select a region.

5. Set the AutoRedraw property of Pic_Dest to True.

6. Add the following code to Module1:

  Public Const INVERSE = 6
  Public Const DOT = 2
  Public Const SOLID = 0

  Public OrigX As Long
  Public OrigY As Long
  Public DestX As Long
  Public DestY As Long

  Public Sub Draw_Selection_Rectangle()
   
      ' Set drawing mode to INVERSE since this routine also used to erase
      ' the selection rectangle by simply drawing over the currently 
      ' displayed rectangle
      
      With Editor.Pic_Edit
          .DrawMode = INVERSE
          .DrawStyle = DOT
          Editor.Pic_Edit.Line (OrigX, OrigY)-(DestX, DestY), , B
          .DrawStyle = SOLID
      End With

  End Sub

  Public Sub Copy_Rectangle()
      With Editor.Pic_Dest
          .Cls
          .Visible = True
          .Height = DestY - OrigY
          .Width = DestX - OrigX
          .PaintPicture Editor.Pic_Edit, 0, 0, (DestX - OrigX), _
              (DestY - OrigY), OrigX, OrigY, (DestX - OrigX), _
              (DestY - OrigY), vbSrcCopy
      End With
      
      ' Make sure the clipboard is clear, then copy the image:
      Clipboard.Clear
      Clipboard.SetData Editor.Pic_Dest.Image
  End Sub

7. Add the following code to Form1:

  Private Sub Pic_Edit_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
      If Button = 1 Then Pic_Edit.Refresh
      Pic_Dest.Visible = False
      OrigX = X
      OrigY = Y
      DestX = OrigX
      DestY = OrigY
      Call Module1.Draw_Selection_Rectangle
  End Sub

  Private Sub Pic_Edit_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
         
      If Button = 1 Then
          DestX = X
          DestY = Y
          Pic_Edit.Refresh
          Call Module1.Draw_Selection_Rectangle
      End If
  End Sub

  Private Sub Pic_Edit_MouseUp(Button As Integer, Shift As Integer, X As Single, Y As Single)
      ' Check to see if mouse moved or goes the "wrong" way:
      If DestX <= OrigX Or DestY <= OrigY Then
          Pic_Edit.Refresh
          Exit Sub
      End If
      
      If Button = 1 Then Call Copy_Rectangle
  End Sub

8. Start the application and select an area of the bitmap with the mouse. When
  you release the mouse button, Pic_Dest appears with the selected region.

NOTE: If you open up MS Paint, MS Word, or any other application that can take a
pasted bitmap image, you are able to paste the selected portion of the image to
that application. You can also view the contents of the clipboard by using the
Clipboard Viewer.

REFERENCES
==========

For additional information, click the article number below to view the article
in the Microsoft Knowledge Base:

  Q71488 How to Create Rubber-Band Lines/Boxes in Visual Basic

Additional query words:

======================================================================
Keywords          : kbBitmap kbClipboard kbCtrl kbVBp kbVBp500 kbVBp600 kbGrpDSVB kbDSupport 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVB600Search kbVBA500 kbVBA600 kbVB500 kbVB600
Version           : WINDOWS:5.0,6.0
Issue type        : kbhowto

=============================================================================

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.

Copyright Microsoft Corporation 1986-2002.