Keypress Event in asp.net

Hi All,
 
Hey, I'm having a text box where the user should not manipulate the data. I've done the coding like this
<asp:TextBox ID="TextBox2" runat="server"  OnKeyPress = "return false" OnCut = "return false" OnCopy = "return false" OnPaste = "return false"></asp:TextBox>
 
This is working perfectly. But the problem is, if i give backspace or delete, the keypress event arise. Why is it so !! Can anyone help !!
...