This post applies to any ASP.NET app that uses .aspx files, whether WebForms or MVC.When you write an aspx/ascx/master file (I’ll just say aspx for here on, but it applies to all), it gets compiled dynamically by the ASP.NET runtime. Note that this is true whether you use a Web Site or a Web Application Project (WAP). While in a WAP, most of the code is built by Visual Studio, the aspx pages themselves are always built dynamically. Normally, when you work with aspx files, you only need to worry about what you write in there, and the specifics of what ASP.NET generates under the cover are somewhat of an implementation details. However, in some cases it’s pretty useful to look at the generated code, either to learn exactly what it does, or to make sense of tricky issues. Note: one case where it’s particularly useful is if you’re implementing ProcessGeneratedCode in a ControlBuilder to generate custom code. In that case, you really need to debug into the generated code if anything goes wrong. For illustration, let’s take a really simple example page, and go through both how we can view the generated code, and then actually debug it.Read more: Angle Bracket Percent