如题:代码如下  
          function dotSelect()
          {
          if($("input[id$='Checkbox1']").attr("checked") == true)
          {
               alert("来了");
               $("#Mytable tr").each(function(){
               
                 $(this).children().eq(4).hide();
               })
          }
          else
          {
             $("Mytable tr").each(function(){
                  $("dis").show();
               })
          }
        }<input id="Checkbox1" type="checkbox" onclick="dotSelect();" />