How do I create a calendar in code-behind?

[hofappots]

I want to create an asp.net ajax calendar like this, but entirely in code-behind. How do I do it?Edit: I only want to add the js code to the page in code-behind (eg: not in the markup)Edit_2: I need this because I create a textbox control in a template class and want to create the calendar there (for use with the textbox)