为什么我的代码返回else语句而未定义，而不是totalBasketballScore

Question

我真的认为我的代码是正确的。我试着用罚球、2分球和3分球来计算篮球得分。当我console.log totalBasketballScore时，输出结果是"所有条目都必须是数字"且未定义。当我把3个值放在参数中时，我需要改变什么才能得到分数？

function totalBasketballScore(numberFreeThrows, numberMidRange, numberThreePointers) {
const freeThrows = 1;
const midRange = 2;
const threePointers = 3;
if (typeof numberFreeThrows === 'number' && numberMidRange === 'number' && numberThreePointers === 'number') {
let totalFreeThrows = freeThrows * numberFreeThrows;
let totalMidRange = midRange * numberMidRange;
let totalThreePointers = threePointers * numberThreePointers;
let gameTotal = totalFreeThrows + totalMidRange + totalThreePointers;
return gameTotal;
} else {
console.log('All Entries Must Be a Number');
}
}
console.log(totalBasketballScore(1, 2, 4));

Answer 1

可以使用的另一种方法是isNaN((。isNaN可用于检查该值是否为非数字。如果isNaN((返回false，则该值是一个数字。

function totalBasketballScore(numberFreeThrows, numberMidRange, numberThreePointers) {
const freeThrows = 1;
const midRange = 2;
const threePointers = 3;
if(isNaN(numberFreeThrows)=== false && isNaN(numberMidRange)=== false && isNaN(numberThreePointers)=== false) {
let totalFreeThrows = freeThrows * numberFreeThrows;
let totalMidRange = midRange * numberMidRange;
let totalThreePointers = threePointers * numberThreePointers;
let gameTotal = totalFreeThrows + totalMidRange + totalThreePointers;
return gameTotal;
} else {
console.log('All Entries Must Be a Number');
}
}
console.log(totalBasketballScore(1, 2, 4));

Answer 2

每个参数都应该使用typeof，如下所示：

if(typeof numberFreeThrows === 'number' && typeof numberMidRange === 'number' && typeof numberThreePointers === 'number'){
} else {
}