Subtract month from 'yyyymm' in js

Subtract month from 'yyyymm' in js

本文关键字:in js yyyymm month Subtract from      更新时间:2023-09-26

如何使用Javascript函数从这种格式的日期中减去一个月?

例如

:201301 -> 201212

function subtractMonth(year_month){
year_month = parseInt(year_month);
if(year_month%100 == 1) return year_month-89;
return year_month-1;
}

试试这样写:

function processDate(dateString){
    var month=dateString%100;
    var year=dateString/100;
    var d=new Date(year,month-1,1,0,0,0,0)
    d.setDate(d.getDate()-2);
    year=d.getFullYear().toString();
    month=("0"+(d.getMonth()+1).toString()).substr(-2);
    document.write(year+month);
}

processDate(201401)应该得到201312