js获取指定yyyy-mm格式的时间

function getNowFormatDate() {  //获取当月时间 yyyy-MM-dd
    var date = new Date();
    var year = date.getFullYear();
    var month = date.getMonth() + 1;
    var strDate = date.getDate();
    if (month >= 1 && month <= 9) {
      month = '0' + month;
    }
    if (strDate >= 1 && strDate <= 9) {
      strDate = '0' + strDate ;
    }
    var currentdate = year + '-' + month + '-' + strDate
    return currentdate;
    // console.log(currentdate);
  }