简化if else语句

Question

嗨我有一个json数据如下:

{
    "details":
        {
            "data1": 
                {
                    "monthToDate":1000,                   
                    "firstLastMonth":"December",
                    "firstLastMonthAmount":5000,
                    "secondLastMonth":"November",
                    "secondLastMonthAmount":12000
                },
            "data2":
                {
                    "monthToDate":4000,                   
                    "firstLastMonth":"December",
                    "firstLastMonthAmount":10000,
                    "secondLastMonth":"November",
                    "secondLastMonthAmount":15000
                },
           "data3":
                {
                    "monthToDate":2000,                   
                    "firstLastMonth":"December",
                    "firstLastMonthAmount":8000,
                    "secondLastMonth":"November",
                    "secondLastMonthAmount":12000
                }
        }   
}

如果下面的陈述,我有打字稿,

....
Object.values(data.details.data1).map(obj => {
                if (obj === 'January') {
                    xAxisTranslatedArray.push(this.JAN);
                } else if (obj === 'February') {
                    xAxisTranslatedArray.push(this.FEB);
                } else if (obj === 'March') {
                    xAxisTranslatedArray.push(this.MAR);
                } else if (obj === 'April') {
                    xAxisTranslatedArray.push(this.APR);
                } else if (obj === 'May') {
                    xAxisTranslatedArray.push(this.MAY);
                } else if (obj === 'June') {
                    xAxisTranslatedArray.push(this.JUN);
                } else if (obj === 'July') {
                    xAxisTranslatedArray.push(this.JUL);
                } else if (obj === 'August') {
                    xAxisTranslatedArray.push(this.AUG);
                } else if (obj === 'September') {
                    xAxisTranslatedArray.push(this.SEP);
                } else if (obj === 'October') {
                    xAxisTranslatedArray.push(this.OCT);
                } else if (obj === 'November') {
                    xAxisTranslatedArray.push(this.NOV);
                } else if (obj === 'December') {
                    xAxisTranslatedArray.push(this.DEC);
                }
            });

我使用lodash,highcharts和i18n翻译.所以我的每一个this.MONTH都是i18n键.我无法直接传递值,因为无法翻译它们.所以我需要将每个值推送到一个数组并传递到highchart的X轴.我的问题基本上是当我看到if else语句看起来太长而且有点重复时.这里有捷径吗？先谢谢你们.

Answer 1

使用单独的地图对象:

const months = {
    January: this.JAN,
    February: this.FEB,
    March: this.MAR,
    // etc,
}

Object.values(data.details.data1).forEach(obj => {
    if (months[obj]) {
        xAxisTranslatedArray.push(months[obj]);
    }
});

或者,你可以更换if一个filter:

Object.values(data.details.data1)
    .filter(obj => months[obj])
    .forEach(obj => xAxisTranslatedArray.push(months[obj]));

另外,请注意我使用的是forEach代替map.map用于修改数组,但您只是在数组上进行迭代.forEach是那里语义正确的选择.