how to call javascript function written in c#, onkeypress of a button in c#

Question

i have written a javascript code in c# given below and i want to call it on 'onkeypress' event on a button in c#, how to do it

void Js()
{
    string js = "<script type='text/javascript' > 
                  function myfunction()
                      { 
                          alert(1); 
                       }
                    </script>";

}

and calling it on page load like

textbox1.Attributes.Add("onKeypress", " return myfunction();");

Answer 1

string js = "string js = "<script type='text/javascript'>"+
                  "function myfunction(){"+
                          "alert(1); "+
                      " } </script>";

Response.Write(js);
textbox1.Attributes.Add("onKeypress", " return myfunction();");