增加年,月,天

增加年数,月数,天数

function DateAdd(interval, number, date) {
    /*
    *   功能:实现JSScript的DateAdd功能.
    *   参数:interval,字符串表达式,表示要添加的时间间隔.
    *   参数:number,数值表达式,表示要添加的时间间隔的个数.
    *   参数:date,时间对象.
    *   返回:新的时间对象.
    *   var   now   =   new   Date();
    *   var   newDate   =   DateAdd( "d ",5,now);
    *---------------   DateAdd(interval,number,date)   -----------------
    */
    switch (interval) {
        case "y ":
        {
            date.setFullYear(date.getFullYear() + number);
            return date;
            break;
        }
        case "q ":
        {
            date.setMonth(date.getMonth() + number * 3);
            return date;
            break;
        }
        case "m ":
        {
            date.setMonth(date.getMonth() + number);
            return date;
            break;
        }
        case "w ":
        {
            date.setDate(date.getDate() + number * 7);
            return date;
            break;
        }
        case "d ":
        {
            date.setDate(date.getDate() + number);
            return date;
            break;
        }
        case "h ":
        {
            date.setHours(date.getHours() + number);
            return date;
            break;
        }
        case "m ":
        {
            date.setMinutes(date.getMinutes() + number);
            return date;
            break;
        }
        case "s ":
        {
            date.setSeconds(date.getSeconds() + number);
            return date;
            break;
        }
        default:
        {
            date.setDate(d.getDate() + number);
            return date;
            break;
        }
    }
}
//调用
var newDate = DateAdd("y ", 1, dtADate);