我对 JAvaScript 数组和对象有疑问

Question

这里是新手。我从 1 周前开始学习一些编码。我的代码遇到了问题。我只想打印分数大于 4 的雇主姓名。

这是我的代码：

const employers = [
  { name: "Adam", score: 5 },
  { name: "Jane", score: 3 },
  { name: "Lucas", score: 3 },
  { name: "Francesca", score: 2 },
  { name: "Mason", score: 4 }
]

function getEmployer(employerList) {
  let List = [employers];
  
  
  for (let i = 0; i < List.length; i++) {
    if(List['score'] > 4 ) {
        return List[i].name;
      }
  }
  
}


console.log(getEmployer(employers))

你能给我一些细节吗？

Answer 1

这是我的做法，与您的做法类似。请参阅各行旁边的注释以获取解释。

const employers = [
  { name: "Adam", score: 5 },
  { name: "Jane", score: 3 },
  { name: "Lucas", score: 3 },
  { name: "Francesca", score: 2 },
  { name: "Mason", score: 4 }
]

function getEmployer(employerList) {
  let list = []; // Empty array to store the results in.
  
  
  for (let i = 0; i < employerList.length; i++) { // Loop over the items in 'employerList', 
    if(employerList[i].score > 4 ) {
        list.push(employerList[i]); // Add the item from employerList to the array with results. 
      }
  }
  return list; // Return the array with results. 
}


console.log(getEmployer(employers))

Answer 2

当您可以使用

for

时，无需在此处使用

forEach

循环 - 您可以直接循环遍历作为参数传递给函数的数组。

此外，还添加了一个数组来保存多个数组元素，其中

score

大于

4

。

const employers = [{
    name: "Adam",
    score: 5
  },
  {
    name: "Jane",
    score: 3
  },
  {
    name: "Lucas",
    score: 3
  },
  {
    name: "Francesca",
    score: 5
  },
  {
    name: "Mason",
    score: 4
  }
]

function getEmployer(employerList) {
  // Let's have a holder for all that are greater than 4.
  let highScore = [];
  
  // Make sure you are actually passing an array.
  if (Array.isArray(employerList)) {
    // Loop through what is passed.
    employerList.forEach((elem) => {
      // If the array element score is greater than 4, let's push it into our highScore array.
      if (elem.score > 4) {
        highScore.push(elem);
      }
    });
  }
  
  // Return it!
  return highScore;
}

console.log(getEmployer(employers));

Answer 3

在代码的这一部分

let List = [employers];

，您将数组参数放入不需要的数组中，并且没有在 if 中传递索引。您可以通过这种方式修复您的代码，但是此解决方案将仅打印第一个匹配项

const employers = [
  { name: "Adam", score: 5 },
  { name: "Jane", score: 3 },
  { name: "Lucas", score: 3 },
  { name: "Francesca", score: 2 },
  { name: "Mason", score: 4 }
]

function getEmployer(employerList) {

  for (let i = 0; i < employerList.length; i++) {
    if(employerList[i]['score'] > 4 ) {
        return employerList[i].name;
      }
  }
  
}


console.log(getEmployer(employers))

您可以通过这种方式返回雇主数组以显示所有匹配项

const employers = [
  { name: "Adam", score: 5 },
  { name: "Jane", score: 3 },
  { name: "Lucas", score: 3 },
  { name: "Francesca", score: 2 },
  { name: "Mason", score: 4 },
  { name: "Lucas2", score: 8 },
  { name: "Francesca2", score: 2 },
  { name: "Mason2", score: 7 }
]

function getEmployer(employerList) {
  let matchedEmployers = [];
  
  employerList.forEach((employer) => {
    if(4 < employer.score) {
      matchedEmployers.push(employer.name)
    }
  })
  return matchedEmployers;
}


console.log(getEmployer(employers))