初学者问题:想知道为什么函数需要重复吗？

Question

因此，我使用JS创建了一个非常基本的bmi计算器。我已经创建了一个函数，然后尝试使用该函数的名称(bmiCalculator)重新调用它。据我所知，这应该会给我带来正确的回报。

我寻找并找到了解决方案，但只是想了解为什么函数需要重复运行函数？

​

function bmiCalculator(weight, height) {

  var bmi = Math.round(weight / Math.pow(height, 2));
  var interpretation;

  if (bmi < 18.5) {
    interpretation = "Your BMI is " + bmi + ", so you are underweight.";
  }

  if (bmi >= 18.5 && bmi < 24.9) {
    interpretation = "Your BMI is " + bmi + ", so you have a normal weight.";
  }

  if (bmi >= 25) {
    interpretation = "Your BMI is " + bmi + ", so you are overweight.";
  }

  return interpretation;

};


bmiCalculator(68, 1.73);

function bmiCalculator(weight, height) {
  var bmi = Math.round(weight / Math.pow(height, 2));
  var interpretation;


  if (bmi < 18.5) {
    interpretation = "Your BMI is " + bmi + ", so you are underweight.";
  }

  if (bmi >= 18.5 && bmi < 24.9) {
    interpretation = "Your BMI is " + bmi + ", so you have a normal weight.";
  }

  if (bmi >= 25) {
    interpretation = "Your BMI is " + bmi + ", so you are overweight.";
  }
  return interpretation
};




bmiCalculator(45, 1.65);

​

Answer 1

不，您不必重复函数。下面的代码应该可以很好地工作：

function bmiCalculator(weight,height) {

    var bmi = Math.round(weight / Math.pow(height,2));
    var interpretation;
    
if (bmi < 18.5) {
    interpretation = "Your BMI is " + bmi + ", so you are underweight.";
}

if (bmi >= 18.5 && bmi < 24.9) {
    interpretation ="Your BMI is " + bmi + ", so you have a normal weight.";
}

if (bmi >= 25) {
    interpretation ="Your BMI is " + bmi + ", so you are overweight.";
}
   
   return interpretation;
    
};
bmiCalculator(68,1.73);
bmiCalculator(45,1.65); 

您可以将结果保存到变量，例如：

const bmi1 = bmiCalculator(68,1.73);
const bmi2 = bmiCalculator(45,1.65);
console.log(bmi1);
console.log(bmi2);

Answer 2

我运行了代码，它工作得很好。您应该使用console.log并查看代码的ruslts。在chrome中，你可以按F12来打开控制台，然后当你使用console.log(bmiCalculator(68,1.73));时，它会打印出BMI。您可以在第一次函数调用后删除代码。