How to close window without prompt. JavaScript.

For most of browsers work code like this:

window.opener = top;
window.close();

But for IE7 will work this code:

<script language=javascript>
function CloseWindow() 
{
  window.open('','_self','');
  window.close();
}
</script>

<input type=button name="closebutton" value="Close" class="Button" onclick="CloseWindow()"/>