如何更改另一个数组中一个数组的值

Question

这是我的学生成绩json文件： （这个想法是创建一个函数来改变特定的学生分数）

const classesData = [
  {
    name: 'A',
    books: [
      { name: 'math' },
      { name: 'chemistry' },
      { name: 'physic' }
    ],
    students: [
      {
        name: 'first student',
        results: [
          { name: 'math', score: '20' },
          { name: 'chemistry', score: '14' },
          { name: 'physic', score: '16' },
        ]
      },
      {
        name: 'second student',
        results: [
          { name: 'math', score: '15' },
          { name: 'chemistry', score: '10' },
          { name: 'physic', score: '12' },
        ]
      }
    ]
  },
  {
    name: 'B',
    books: [
      { name: 'math' },
      { name: 'chemistry' },
      { name: 'physic' }
    ],
    students: [
  {
        name: 'first student',
        results: [
          { name: 'math', score: '20' },
          { name: 'chemistry', score: '14' },
          { name: 'physic', score: '16' },
        ]
      },
      {
        name: 'second student',
        results: [
          { name: 'math', score: '15' },
          { name: 'chemistry', score: '10' },
          { name: 'physic', score: '12' },
        ]
      }
    ]
  }
]

怎么做呢？ 例如 从班级A将第二个学生物理分数从12更改为20 我尝试过 foreach 和 map 但没有得到我想要的结果

Answer 1

要编写一个更新特定学生特定科目分数的函数，我们应该将四个参数传递给该函数：

function patchScore(data, student, subject, score) {}

为了方便，我们将返回更改后的数据。

在实现下面，你可以写得更短，但我更喜欢可读性。请记住，我只遵循“快乐之路”，如果（例如）找不到学生，您最好添加一些验证。

const classesData = [
  {
    name: 'A',
    books: [
      { name: 'math' },
      { name: 'chemistry' },
      { name: 'physic' }
    ],
    students: [
      {
        name: 'first student',
        results: [
          { name: 'math', score: '20' },
          { name: 'chemistry', score: '14' },
          { name: 'physic', score: '16' },
        ]
      },
      {
        name: 'second student',
        results: [
          { name: 'math', score: '15' },
          { name: 'chemistry', score: '10' },
          { name: 'physic', score: '12' },
        ]
      }
    ]
  },
  {
    name: 'B',
    books: [
      { name: 'math' },
      { name: 'chemistry' },
      { name: 'physic' }
    ],
    students: [
  {
        name: 'first student',
        results: [
          { name: 'math', score: '20' },
          { name: 'chemistry', score: '14' },
          { name: 'physic', score: '16' },
        ]
      },
      {
        name: 'second student',
        results: [
          { name: 'math', score: '15' },
          { name: 'chemistry', score: '10' },
          { name: 'physic', score: '12' },
        ]
      }
    ]
  }
]

let patchedData = patchScore(classesData, 'first student', 'math', 1);
console.log(patchedData)

function patchScore(data, student, subject, score) {

  // Find student
  let matchedStudent = data[0].students.find((s) => s.name === student)
  
  // Find subject
  let matchedSubject = matchedStudent.results.find((s) => s.name === subject)
  
  // Update score
  matchedSubject.score = score
  
  return data;
  
}