function CheckAllup(form)
   {
        for (var i=0;i<form.elements.length;i++)
        {
        var e = form.elements[i];
        if (e.Name != "chkAll")
            e.checked = form.chkAllup.checked;
        }
   }
   
   function CheckAlldown(form)
   {
        for (var i=0;i<form.elements.length;i++)
        {
        var e = form.elements[i];
        if (e.Name != "chkAll")
            e.checked = form.chkAlldown.checked;
        }
   }
   function checkbox()
   {
	       var ids = document.getElementsByName("postid");
	       var check=false;
	       var a=0;
	      if (ids != null) 
	      {
		    for (i=0; i<ids.length; i++) 
		    {
			  var obj = ids[i];
			   if (obj.checked==true)
			   {
				check=true;
				a+=1
			   }
		    }
		      if(check==false){return false;}
	      }   
   }