如何从数组中删除特定项目? [英] How can I remove a specific item from an array?

问题描述

我有一个数字数组，并且正在使用.push()方法向其中添加元素.

I have an array of numbers and I'm using the .push() method to add elements to it.

是否有一种简单的方法可以从数组中删除特定元素?

Is there a simple way to remove a specific element from an array?

我正在寻找类似的东西:

I'm looking for the equivalent of something like:

array.remove(number);

我必须使用 core JavaScript.不允许使用框架.

I have to use core JavaScript. Frameworks are not allowed.

推荐答案

使用

splice()方法通过删除来更改数组的内容 现有元素和/或添加新元素.

The splice() method changes the contents of an array by removing existing elements and/or adding new elements.

const array = [2, 5, 9];

console.log(array);

const index = array.indexOf(5);
if (index > -1) {
  array.splice(index, 1);
}

// array = [2, 9]
console.log(array); 

splice的第二个参数是要删除的元素数.请注意，splice会在适当位置修改数组，并返回一个包含已删除元素的新数组.

The second parameter of splice is the number of elements to remove. Note that splice modifies the array in place and returns a new array containing the elements that have been removed.

出于完整性的原因，这里有一些功能.第一个功能仅删除一个匹配项(即从[2,5,9,1,5,8,5]中删除5的第一个匹配项)，而第二个功能则删除所有匹配项:

For the reason of completeness, here are functions. The first function removes only a single occurrence (i.e. removing the first match of 5 from [2,5,9,1,5,8,5]), while the second function removes all occurrences:

function removeItemOnce(arr, value) {
  var index = arr.indexOf(value);
  if (index > -1) {
    arr.splice(index, 1);
  }
  return arr;
}

function removeItemAll(arr, value) {
  var i = 0;
  while (i < arr.length) {
    if (arr[i] === value) {
      arr.splice(i, 1);
    } else {
      ++i;
    }
  }
  return arr;
}
//Usage
console.log(removeItemOnce([2,5,9,1,5,8,5], 5))
console.log(removeItemAll([2,5,9,1,5,8,5], 5))

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