JavaScript 函数没有执行预期的操作

Question

该函数在调用时没有抛出预期的输出。 return 语句不起作用。

我逐行检查代码错误。

function checkDriverAge(age) {
  if(Number(age) < 18) {
    var x = "Sorry you are to yound to drive this car. Powering off";
    return x;
  } else if(Number(age) === 18) {
    var y = "Congratulations of your first year of driving. Enjoy de ride";
    return y;
  } else if(Number(age) > 18) {
    var z = "Powering On. Enjoy the ride!";
    return z;
  }
}

checkDriverAge(prompt("Input an age"));

预期结果是输出相对于输入年龄的相应“if”内指定的字符串。

Answer 1

因此，按照代码的编写方式，来自 checkDriverAge(prompt("Input anage")); 的值不会被分配给任何内容。

尝试将其分配给变量、将其注销或警告该值。

console.log(checkDriverAge(prompt("Input an age")));
var x = checkDriverAge(prompt("Input an age"));
alert(checkDriverAge(prompt("Input an age")));