Este codigo se debe usar con una barra de menus, ahi van los ejemplos
Private Sub MnuCopiar_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MnuCopiar.Click
Dim Frm As MiForm = Me.ActiveMdiChild
If (Not Frm Is Nothing) Then
Try
Dim txtRichTextBox As RichTextBox = CType(Frm.ActiveControl, RichTextBox)
If (Not txtRichTextBox Is Nothing) Then
Clipboard.SetDataObject(txtRichTextBox.SelectedText)
End If
Catch
Exit Try
End Try
End If
End Sub
Private Sub MnuPegar_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MnuPegar.Click
Dim Frm As MiForm = Me.ActiveMdiChild
If (Not Frm Is Nothing) Then
Try
Dim txtRichTextBox As RichTextBox = CType(Frm.ActiveControl, RichTextBox)
If (Not txtRichTextBox Is Nothing) Then
Dim data As IDataObject = Clipboard.GetDataObject()
If (data.GetDataPresent(DataFormats.Text)) Then
txtRichTextBox.SelectedText = data.GetData(DataFormats.Text).ToString()
End If
End If
Catch
Exit Try
End Try
End If
End Sub