ES1010

该员额汇总了截至2001年1月1日从数组中删除元素的通用方法ECMAScript 2019(ES10)。

1. 普通案件

1.1. 使用数值删除矩阵元素.splice()

| 在职:是________________________________________________________________________________________________________________________________________________________________________________________________________
| 删除重复: 是( loop) , 否( indexof)
| 按值/ 指数:按指数:___________________________________________________________________________________________________________________________________________________________________________________

如果您知道要从数组中删除的值, 您可以使用复数法。 首先, 您必须确定目标项的索引。 然后使用索引作为起始元素, 并删除一个元素 。

// With a 'for' loop
const arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0];
for( let i = 0; i < arr.length; i++){
  if ( arr[i] === 5) {
    arr.splice(i, 1);
  }
} // => [1, 2, 3, 4, 6, 7, 8, 9, 0]

// With the .indexOf() method
const arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0];
const i = arr.indexOf(5);
arr.splice(i, 1); // => [1, 2, 3, 4, 6, 7, 8, 9, 0]

1.2. 使用.filter()方法

| 在职: 否 ____________________________________________________________________________________________________________________________________________________________________________________________________________
| 删除重复:是________________________________________________________________________________________________________________________________________________________________________________________________________
| 按值/ 指数: 按数值 :%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

具体要素可以是已经过滤从数组中,通过提供过滤功能,从数组中取出。然后对数组中的每个元素要求使用此函数。

const value = 3
let arr = [1, 2, 3, 4, 5, 3]
arr = arr.filter(item => item !== value)
console.log(arr)
// [ 1, 2, 4, 5 ]

1.3. 通过扩展来删除队列元素Array.prototype

| 在职:是/否(取决于执行情况)__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
| 删除重复:是/否(取决于执行情况)__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
| 按值/ 指数:按指数 / 按数值(视执行情况而定)

阵列原型可以通过其他方法扩展,然后在创建的阵列上使用这些方法。

注:一些人认为,从JavaScript标准图书馆(如Array)扩展物体原型是反型。

// In-place, removes all, by value implementation
Array.prototype.remove = function(item) {
    for (let i = 0; i < this.length; i++) {
        if (this[i] === item) {
            this.splice(i, 1);
        }
    }
}
const arr1 = [1,2,3,1];
arr1.remove(1) // arr1 equals [2,3]

// Non-stationary, removes first, by value implementation
Array.prototype.remove = function(item) {
    const arr = this.slice();
    for (let i = 0; i < this.length; i++) {
        if (arr[i] === item) {
            arr.splice(i, 1);
            return arr;
        }
    }
    return arr;
}
let arr2 = [1,2,3,1];
arr2 = arr2.remove(1) // arr2 equals [2,3,1]

1.4. 使用delete操作员

| 在职:是________________________________________________________________________________________________________________________________________________________________________________________________________
| 删除重复: 否 ____________________________________________________________________________________________________________________________________________________________________________________________________________
| 按值/ 指数:按指数:___________________________________________________________________________________________________________________________________________________________________________________

使用删除运算符不会影响长度属性。 它也不会影响后续元素的索引。 数组变得稀少, 这是一种巧妙的方式, 表示删除的项目没有被删除, 但却没有定义 。

const arr = [1, 2, 3, 4, 5, 6];
delete arr[4]; // Delete element with index 4
console.log( arr ); // [1, 2, 3, 4, undefined, 6]

删除运算符的设计是为了从 JavaScript 对象中删除属性,而数组则是对象。

1.5. 使用Object公用事业(ES10)

| 在职: 否 ____________________________________________________________________________________________________________________________________________________________________________________________________________
| 删除重复:是________________________________________________________________________________________________________________________________________________________________________________________________________
| 按值/ 指数: 按数值 :%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

A. 实行ES-1010Object.fromEntries,可以用来从任何类似阵列的物体中创建所需的阵列,并在过程中过滤不想要的元素。

const object = [1,2,3,4];
const valueToRemove = 3;
const arr = Object.values(Object.fromEntries(
  Object.entries(object)
  .filter(([ key, val ]) => val !== valueToRemove)
));
console.log(arr); // [1,2,4]

2. 特殊情况

2.1 如果在阵列末端,则删除元素

2.1.1. 变化阵列length

| 在职:是________________________________________________________________________________________________________________________________________________________________________________________________________
| 删除重复: 否 ____________________________________________________________________________________________________________________________________________________________________________________________________________
| 按值/ 指数:不适用_______________________________________________________________________________________________________________________________________________________________________________________________________________________

JavaScript 阵列元素可以通过将长度属性设定为低于当前值的值,从数组的末尾删除。任何指数大于或等于新长度的元素将被删除 。

const arr = [1, 2, 3, 4, 5, 6];
arr.length = 5; // Set length to remove element
console.log( arr ); // [1, 2, 3, 4, 5]

2.1.2. 使用.pop()方法

| 在职:是________________________________________________________________________________________________________________________________________________________________________________________________________
| 删除重复: 否 ____________________________________________________________________________________________________________________________________________________________________________________________________________
| 按值/ 指数:不适用_______________________________________________________________________________________________________________________________________________________________________________________________________________________

流行方法删除数组最后一个元素, 返回该元素, 并更新长度属性。 流行方法修改援引该元素的数组, 这意味着与使用删除最后一个元素的方式不同, 将完全删除最后一个元素, 并缩小数组长度 。

const arr = [1, 2, 3, 4, 5, 6];
arr.pop(); // returns 6
console.log( arr ); // [1, 2, 3, 4, 5]

2.2. 如果在阵列开始时,则删除元素

| 在职:是________________________________________________________________________________________________________________________________________________________________________________________________________
| 删除重复: 否 ____________________________________________________________________________________________________________________________________________________________________________________________________________
| 按值/ 指数:不适用_______________________________________________________________________________________________________________________________________________________________________________________________________________________

缩略.shift()方法与流行法非常相似, 但它删除了 JavaScript 数组的第一个元素, 而不是最后一个元素。 当元素被删除时, 其余元素会被移到下方 。

const arr = [1, 2, 3, 4];
arr.shift(); // returns 1
console.log( arr ); // [2, 3, 4]

2.3. 删除元素,如果它是阵列中唯一的元素

| 在职:是________________________________________________________________________________________________________________________________________________________________________________________________________
| 删除重复:不适用_______________________________________________________________________________________________________________________________________________________________________________________________________________________
| 按值/ 指数:不适用_______________________________________________________________________________________________________________________________________________________________________________________________________________________

最快的技术是设置空数组的数组变量。

let arr = [1];
arr = []; //empty array

2.1.1的替代技术可通过将长度设定为0来使用。

ES6且无突变:(2016年10月)

const removeByIndex = (list, index) =>
      [
        ...list.slice(0, index),
        ...list.slice(index + 1)
      ];
         
output = removeByIndex([33,22,11,44],1) //=> [33,11,44]
      
console.log(output)

Array.prototype.remove = function(x) {
    var y=this.slice(x+1);
    var z=[];
    for(i=0;i<=x-1;i++) {
        z[z.length] = this[i];
    }

    for(i=0;i<y.length;i++){
        z[z.length]=y[i];
    }

    return z;
}

var index,
    input = [1,2,3],
    indexToRemove = 1;
    integers = [];

for (index in input) {
    if (input.hasOwnProperty(index)) {
        if (index !== indexToRemove) {
            integers.push(result); 
        }
    }
}
input = integers;

此解决方案将需要一系列输入, 并将通过输入查找要删除的值。 这将在整个输入数组中循环, 结果将是第二个已经删除了特定索引的数组整数组。 然后将整数组复制到输入数组中 。

我还有一个从阵列中移除的好办法:

var words = ['spray', 'limit', 'elite', 'exuberant', 'destruction', 'present'];

const result = words.filter(word => word.length > 6);

console.log(result);
// expected output: Array ["exuberant", "destruction", "present"]

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/filter