Sometimes you need to find out that if the urls on the page exists or not. The following code reads the HTML of the page and extracts all the urls and finally checks if the url exists or not.
http://geekswithblogs.net/azamsharp/archive/2006/06/08/81251.aspx

Disabling the Button While the User Wait
this.MyButton.Attributes.Add("onclick", "this.value='Please wait...' ;this.disabled = true;" + ClientScript .GetPostBackEventReference(this.MyButton, ""));
http://geekswithblogs.net/azamsharp/archive/2006/06/11/81513.aspx

Mohammad Azam
http://aspalliance.com/author.aspx?uId=58748