发送验证码定时器

// 	手机倒计时验证码
			$(function(){
				var flag = true;
		 		$("#btn").click(function(){
		 			if($('#phone').val() == null || $('#phone').val() =="" || isPhoneNo($.trim($('#phone').val())) == false){
		 				$("#tipPhone").html("手机号不能为空！");
		 			}else{
		 				$("#tipPhone").html("");
		 				var codename  =  $(".codename").val();
			 			$.ajax({
						     type: 'POST',
						     url: 'my.php?mid=10&action=post_code',
						     dataType: 'json',
						     data:{mobile:codename},
						     success: function(data){
						     	console.log(data);
						     },
						     error: function(){
						     	console.log("error");
						     }
						});
		 				timerInt();
		 			}
				
		 		})
		 	});




             function timerInt(){
		 		var index = 60;
		 		$("#btn").val("重新发送(" + index + ")");
		 		var timer =	setInterval(function(){
		 			index--;
		 			if(index < 0){
			 			index = 0;
			 			clearInterval(timer);
			 			$("#btn").val("获取").removeAttr("disabled");
			 			return;
		 			}
		 			$("#btn").val("重新发送(" + index + ")").attr("disabled","disabled");
		 		},1000);
		 	}