計算月份差方法封裝

monthDateFun(startDate, endDate) {  function formatDatetime(datetimeString) {//日期格式化 兼容移動端IOS跟安卓日期出現的NAN    var datetime;    if (isNaN(Date.parse(datetimeString))) {      datetime = datetimeString && new Date(Date.parse(datetimeString.replace(/-/g, '/').replace(/T/g, ' ')));    } else {      datetime = datetimeString && new Date(Date.parse(datetimeString));    }    return datetime;  }  var sdate = formatDatetime(startDate);//格式化日期  var starDateText = formatDatetime(endDate);//格式化日期  var totalMonth;  var starTime = (sdate && (sdate.getFullYear() + "-" + (sdate.getMonth() + 1) + "-" + sdate.getDate())) || '';  var endTime = (starDateText && (starDateText.getFullYear() + "-" + (starDateText.getMonth() + 1) + "-" + starDateText.getDate())) || '';  // 拆分年月日  starTime = starTime.split('-');  // 獲得月數  starTime = parseInt(starTime[0]) * 12 + parseInt(starTime[1]);  // 拆分年月日  endTime = endTime.split('-');  // 獲得月數  endTime = parseInt(endTime[0]) * 12 + parseInt(endTime[1]);  totalMonth = Math.abs(starTime - endTime);  return totalMonth || 0;},