获取焦点光标在文字后边

     $(".pinglun_huifu2_talk_about").live('click',function(){
		 uname=$(this).attr("username");
		 $("#pinglucon").focus();//这个获取焦点一定要放在获取值的前面
		 var a=$("#pinglucon").val();
		 $("#pinglucon").val(a+"@"+uname+" ");
     });