Question

如果我的.json文件包含以下内容：

[
         {
                    "id": "1234",
                    "day": "Monday",
                    "course": "Math110",

         },
         {
                    "id": "1234",
                    "day": "Wednesday",
                    "title": "Math110",

         },
         {
                    "id": "1345",
                    "day": "Tuesday",
                    "title": "Economics210",

         }
]

如何删除id为＃34; 1234＆＃34;的所有对象？在Javascript？ （注意有两个具有相同ID的对象）

delete["1234"]会有效吗？

Answer 1

使用.filter过滤掉数组元素：

＆＃13;

const input = [{
    "id": "1234",
    "day": "Monday",
    "course": "Math110",

  },
  {
    "id": "1234",
    "day": "Wednesday",
    "title": "Math110",

  },
  {
    "id": "1345",
    "day": "Tuesday",
    "title": "Economics210",

  }
];
const output = input.filter(({ id }) => id !== '1234');
console.log(output);

＆＃13;

Answer 2

您可以将JSON解析为数组，然后使用Array.prototype.filter获取一个新数组，该数组没有ID为"1234"的对象：

＆＃13;

const json = '[{"id":"1234","day":"Monday","course":"Math110"},{"id":"1234","day":"Wednesday","title":"Math110"},{"id":"1345","day":"Tuesday","title":"Economics210"}]';

const result = JSON.parse( json ).filter( obj => obj.id !== "1234" );

console.log( JSON.stringify( result, null, ' '.repeat(8) ) );

＆＃13;

Answer 3

您无法使用delete运算符，因为它位于deleting a property in an object。您实际上想要删除数组中的对象。

使用旧的for循环和Array.splice()：

＆＃13;

var inputArray = [{
    "id": "1234",
    "day": "Monday",
    "course": "Math110",

  },
  {
    "id": "1234",
    "day": "Wednesday",
    "title": "Math110",

  },
  {
    "id": "1345",
    "day": "Tuesday",
    "title": "Economics210",

  }
];

var deleteId = "1234";

for (var i = 0; i < inputArray.length; i++) {
  if (inputArray[i].id === deleteId) {
    inputArray.splice(i, 1);
    i = i-1;
  }
}

console.log(inputArray);

＆＃13;

注意：如果您可以创建另一个数组而不修改现有数组，请使用其他答案中提到的Array.filter()。

Answer 4

您必须通过指定数组中项目的位置来删除：

const arr = [{
    "id": "1234",
    "day": "Monday",
    "course": "Math110",

  },
  {
    "id": "1234",
    "day": "Wednesday",
    "title": "Math110",

  },
  {
    "id": "1345",
    "day": "Tuesday",
    "title": "Economics210",

  }
];
arr.forEach(function(item, i){
  if(item.id == "1234")
    delete arr[i];
});

console.log(arr.filter(j => j))

Answer 5

您可以使用过滤方法：https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/filter

items = [
    {
        "id": "1234",
        "day": "Monday",
        "course": "Math110",

    },
    {
         "id": "1234",
         "day": "Wednesday",
         "title": "Math110",

    },
    {
         "id": "1345",
         "day": "Tuesday",
         "title": "Economics210",

     }
];

items.filter(function(item) { 
   return item.id !== '1234';  
});

如何删除具有相同id的两个json对象

5 个答案: