What calls Page_Load and how does it do it?

Question

Page_Load isn\'t a virtual method. What calls this method and how does it do it? Is it reflection or some other technique? Also how many events are handled this way?

Answer 1

The OnLoad method somewhere up the Page hierarchy calls the events assigned to Load (via +=).

The naming Page_Load is just a convention. In AutoEventWireUp mode (i.e. no event handler explicitly declared) this convention is used to find event handlers by their names.

If you have .Net1 available, you can see how the designer adds code to the page's OnInit() to add all components of the page and set

this.Load += new System.EventHandler(this.Page_Load);

.Net2 still does that, but in a separate file which is hidden somewhere under the Windows\Microsoft.Net\Framework\v*\Temporary ASP.Net Files.

I find this chart on ASP.Net Page Life Cycle very useful.