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文章用于扩宽思维倒是不错，工作中还是该写 if 就 if，既然有为何不用，逻辑简单清晰明了。

统计数组中的奇数

假设我们有一个整数数组arrayNum，现在需要统计其中奇数的个数：

const arrayNum = [1, 4, 5, 9, 0, -1, 5];

function getOddCount1(arrayNum){
    //with if
    let count = 0;
    arrayNum.forEach((num) => {
        let value = Math.abs(num % 2);
        if (value === 1) {
            count++;
        }
    });
    return count;
}

function getOddCount2(arrayNum){
    //without if
    let count = 0;
    arrayNum.forEach((num) => {
        let value = Math.abs(num % 2);
        count += value;
    });
    return count;
}
getOddCount1(arrayNum);
getOddCount2(arrayNum);

判断工作日和周末

给定一个日期(比如new Date())，判断它是工作日还是周末，分别返回”weekend”和”weekday”。

const getWeekendOrWeekday1 = (inputDate) => {
  //with if
  const day = inputDate.getDay();

  if (day === 0 || day === 6) {
    return 'weekend';
  } 
  return 'weekday';

  // Or, for ternary fans:
  // return (day === 0 || day === 6) ? 'weekend' : 'weekday';
};

const getWeekendOrWeekday2 = (inputDate) => {
    //without if
    const day = inputDate.getDay();
    switch (day) {
    case 0:
        return 'weekend';
    case 6:
        return 'weekend';
    default:
        return 'weekday';
    }
};

const getWeekendOrWeekday3 = (inputDate) => {
    //without if
    let labels = {
        0: 'weekend',
        6: 'weekend',
        default: 'weekday'
    };
    //without if
    const day = inputDate.getDay();
    return labels[day] || labels['default'];
};

var date = new Date();
getWeekendOrWeekday1(date);
getWeekendOrWeekday2(date);
getWeekendOrWeekday3(date);