js年月日转秒数

日期转秒数：

function formartDateTime(dateStr) {
    
    
		  dateStr = dateStr.replace(/-/g, '/')
		  dateStr = dateStr+" 00:00:00"
		  var timestamp = new Date(dateStr).getTime();
		  return timestamp
		}
	formartDateTime(2021/01/01)