电子邮件的校验

                      //电邮      
                      var pat=/^[a-zA-Z0-9_\-\.]+@[a-zA-Z0-9_\-\.]+\.[a-zA-Z]{0,4}$/;
                      if(!$("#TextBox6")[0].value.match(pat))
                      {
                         ret=false;
                          $("#TextBox6").css({border:"1px solid red"});
                      }