格式化日期 DATE

function formatDate(date, format) {
	if (arguments.length < 2 && !date.getTime) {
		format = date;
		date = new Date();
	}
	typeof format != 'string' && (format = 'YYYY年MM月DD日 hh时mm分ss秒');
	var week = ['Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', '日', '一', '二', '三', '四', '五', '六'];
	return format.replace(/YYYY|YY|MM|DD|hh|mm|ss|星期|周|www|week/g, function(a) {
		switch (a) {
		case "YYYY": return date.getFullYear();
		case "YY": return (date.getFullYear()+"").slice(2);
		case "MM": return date.getMonth() + 1;
		case "DD": return date.getDate();
		case "hh": return date.getHours();
		case "mm": return date.getMinutes();
		case "ss": return date.getSeconds();
		case "星期": return "星期" + week[date.getDay() + 7];
		case "周": return "周" +  week[date.getDay() + 7];
		case "week": return week[date.getDay()];
		case "www": return week[date.getDay()].slice(0,3);
		}
	});
}

格式化日期

tvv2 = formatDate(new Date(tv2), 'YYYY-MM-DD');

tvv2 = formatDate(new Date(), 'YYYY-MM-DD');

tvv2 = formatDate('YYYY-MM-DD');