c# - how can create top border in TemplateField element? -

i create templatefield in project , need set top border of templatefield.

here declare templatefield:

  var myfootertemplate = new templatefield();

and here how try create top border:

   myfootertemplate.itemstyle.cssclass =  "border-top: solid red;";

but attitude doesn't work.

any idea how can create top border in templatefield element?

LP