Adding css class through aspx code behind

Question

I am using aspx. If I have HTML as follows:

I am hoping to dynamically add a css class through the

Answer 1

Assuming your div has some CSS classes already...

The following won't replace existing definitions:

ClassMe.CssClass += " second";

And if you are not sure until the very last moment...

string classes = ClassMe.CssClass;
ClassMe.CssClass += (classes == "") ? "second" : " second";