Question

I have one asp.net application, in which i have one text box for entering home page url. By default this text box contains http://. If the user entered additional text rather than the existing text, it will make the validation. Otherwise leave it as it is. How it possible? Please help me by providing the regular expression for resolving this issue.

Answer 1

Try this expression

^(ht|f)tp(s?)\:\/\/[0-9a-zA-Z]([-.\w]*[0-9a-zA-Z])*(:(0-9)*)*(\/?)([a-zA-Z0-9\-\.\?\,\'\/\\\+&%\$#_]*)?$

From http://msdn.microsoft.com/en-us/library/ff650303.aspx#paght000001_commonregularexpressions

Or this mechanism in code behind

public bool IsValidUri(string uri)
{
  Uri validatedUri;
  return Uri.TryCreate(uri, UriKind.RelativeOrAbsolute, out validatedUri);
}

Posted by 0xA3 here Is there a URL validator on .Net?

HTH