function formatDate(date) {
	console.log(date);
	// date = new Date();

	date = new Date(Date.parse(date.replace(/-/g, "/"))); //转换成Data();
	console.log(date);

	var y = date.getFullYear();
	console.log(y);

	var m = date.getMonth() + 1;
	m = m < 10 ? '0' + m : m;

	var d = date.getDate();
	d = d < 10 ? ('0' + d) : d;
	return y + '-' + m + '-' + d;
}

Date.prototype.format = function (fmt) {
	var o = {
		"M+": this.getMonth() + 1, //月份
		"d+": this.getDate(), //日
		"h+": this.getHours(), //小时
		"m+": this.getMinutes(), //分
		"s+": this.getSeconds(), //秒
		"q+": Math.floor((this.getMonth() + 3) / 3), //季度
		"S": this.getMilliseconds() //毫秒
	};

	if (/(y+)/.test(fmt)) {
		fmt = fmt.replace(RegExp.$1, (this.getFullYear() + "").substr(4 - RegExp.$1.length));
	}

	for (var k in o) {
		if (new RegExp("(" + k + ")").test(fmt)) {
			fmt = fmt.replace(RegExp.$1, (RegExp.$1.length == 1) ? (o[k]) : (("00" + o[k]).substr(("" + o[k]).length)));
		}
	}

	return fmt;
}

方法二调用：new Date(addtime).format("yyyy-MM-dd"); //addtime这个是时间字符