function Check_act(){
			var obj=document.index_form;
			if(obj.card_username.value=="" || obj.card_userpwd.value==""){
			   alert("请正确输入上网卡用户名和密码！");
			   obj.card_username.value='';
			   obj.card_userpwd.value='';
			   obj.card_username.focus();
			   return false;
			}
			if(obj.degree.value==0){
			   alert("请选择身份登录！");
			   obj.degree.focus();
			   return false;
			}
			return true;
		}