Opening a new window in ASP.NET

The following simple HTML code can be used to open a new windows:

<form id="Form1">
 <INPUT Type="button" OnClick="window.open('http://www.google.com')" value="enter">
 </form>

If server side control is a must, do the following at the page load:

button1.Attributes.Add("onclick", "window.open('http://www.google.com')");