Here is a nice trick to help you to detect hackers in action while trying to hack your web applications. The idea is very simple, we want to set a layer there between your application and the internet to watch the web traffic for anything suspicious. These suspicious things might be a query string that contains a XSS script or a SQL injection query. So we will monitor the web traffic that is passing through that layer for well known and common patterns of attack methods that most hackers use to scan your web applications for vulnerabilities. We will use http modules to implement that layer, here is some dirty code to demonstrate the idea.