如何对数组中相同key统一赋值？

Question

有以下两个数组， 其中'name'后缀的数字由arr决定。arr数组有多长，array里的name就有多少个

              let arr=[0,1,2,3];
              
              let array=[
                {
                  name0:'1',
                  name1:'',
                  name2:'',
                  name3:'',
                },
                {
                  name0:'',
                  name1:'',
                  name2:'2',
                  name3:'',
                },
                {
                  name0:'',
                  name1:'6',
                  name2:'',
                  name3:'',
                },
                {
                  name0:'',
                  name1:'',
                  name2:'',
                  name3:'9',
                },
              ]

如何使得数组中相同key的value一样，效果如下

       array=[
                {
                  name0:'1',
                  name1:'6',
                  name2:'2',
                  name3:'9',
                },
                {
                  name0:'1',
                  name1:'6',
                  name2:'2',
                  name3:'9',
                },
                {
                  name0:'1',
                  name1:'6',
                  name2:'2',
                  name3:'9',
                },
                {
                  name0:'1',
                  name1:'6',
                  name2:'2',
                  name3:'9',
                },
              ]

Answer 1

let arr = [0, 1, 2, 3];

let array = [
  {
    name0: '1',
    name1: '',
    name2: '',
    name3: '',
  },
  {
    name0: '',
    name1: '',
    name2: '2',
    name3: '',
  },
  {
    name0: '',
    name1: '6',
    name2: '',
    name3: '',
  },
  {
    name0: '',
    name1: '',
    name2: '',
    name3: '9',
  },
];


let values = {};

// 遍历数组，更新values对象
array.forEach(item => {
  arr.forEach((_, index) => {
    let key = 'name' + index;
    if (item[key]) {
      values[key] = item[key];
    }
  });
});

array = array.map(() => {
  let newObj = {};
  arr.forEach((_, index) => {
    let key = 'name' + index;
    newObj[key] = values[key] || '';
  });
  return newObj;
});

console.log(array);

Answer 2

我假设你希望将所有非空键的值分配给其他相同键的项。如果这是你的需求，你可以用循环来实现。以下是一个例子：

let array=[
    {name0:'1', name1:'', name2:'', name3:''},
    {name0:'', name1:'', name2:'2', name3:''},
    {name0:'', name1:'6', name2:'', name3:''},
    {name0:'', name1:'', name2:'', name3:'9'}
];

for(let i = 0; i < array.length; i++) {
    for(let key in array[i]) {
        if(array[i][key] !== '') {
            for(let j = 0; j < array.length; j++) {
                if(array[j][key] === '') {
                    array[j][key] = array[i][key];
                }
            }
        }
    }
}

console.log(array);

Answer 3

用HashMap