javascript全选

(1)

function CheckBox_SeleAll(obj)
    {
          if(obj.type =="checkbox"&&obj.checked ==true)
          {
     
       for(i=0;i<document.all.length;i++)
         {
          if(document.all.item(i).type=="checkbox")
           {
           document.all.item(i).checked = true;
           }
            }
      }
      else
      {
         for(i=0;i<document.all.length;i++)
            {
             if(document.all.item(i).type=="checkbox")
              {
              document.all.item(i).checked = false;
              }
               }
         }
       // alert(document.all.length);
      }

 

(2)

function checkAll(obj){  
  var setTrue = false;
  if(obj.checked){
   setState = true;
  }else{
   setState = false;
  }
  
  var c = document.getElementsByName("cc");
  
  for(var i=0; i<c.length; i++){
   c[i].checked = setState;
  }
 }

 

3:

function selectallclient(obj)

{ var table = document.getElementById("DGcontact");

 var ins = table.getElementsByTagName('input');

 for(i = 0; i < ins.length; i ++)

{ if(ins[i].type.toLowerCase() == 'checkbox')

{ ins[i].checked = obj.checked; } } }