Visual Basic Concepts
You can use the GetFormat method to determine whether the data on the Clipboard is in a particular format. For example, you can disable the Paste command depending on whether the data on the Clipboard is compatible with the currently active control.
Private Sub mnuEdit_Click ()
' Click event for the Edit menu.
mnuCut.Enabled = True
mnuCopy.Enabled = True
mnuPaste.Enabled = False
If TypeOf Screen.ActiveControl Is TextBox Then
If Clipboard.GetFormat(vbCFText) Then mnuPaste.Enabled = True
ElseIf TypeOf Screen.ActiveControl Is ComboBox Then
If Clipboard.GetFormat(vbCFText) Then mnuPaste.Enabled = True
ElseIf TypeOf Screen.ActiveControl Is ListBox Then
If Clipboard.GetFormat(vbCFText) Then mnuPaste.Enabled = True
ElseIf TypeOf Screen.ActiveControl Is PictureBox _
Then
If Clipboard.GetFormat(vbCFBitmap) Then mnuPaste.Enabled = True
Else
' Can't cut or copy from the other types
' of controls.
mnuCut.Enabled = False
mnuCopy.Enabled = False
End If
End Sub
Note You might also want to check for other data formats with the constants vbCFPalette, vbCFDIB, and vbCFMetafile. If you want to replace a picture’s palette using Clipboard operations, you should request vbCFBitmap rather than vbCFDIB from the Clipboard. See "Working with 256 Colors" later in this chapter for more information on working with the color palette.
For More Information See "Clipboard Object" in the Language Reference.