title: Extending/overriding existing ASP.NET controls
body: <p>I have a project with a whole bunch of labels, text boxes, and other web controls. There are literally hundreds of them.</p>
  
  <p>I want now to be able to override certain properties in order to run content through an anti-XSS library. For example, when I set the text property of a label using data from a database I want to automatically run a function to scrub out any potentially malicious code.</p>
  
  <p>I also tried overriding the text property using a class that implements IExtenderProvider but I could't get it to help.</p>
  
  <p>Had I been building this from scratch I may have opted to create a new label class that inherits the system label class. Due to the size of the project I would rather not do that.</p>
  
  <p>Any thoughts? </p>