如何从数组中删除n而不对其进行突变？

Question

您好，这个问题需要删除

Answer 1

您可以使用filter或reduce，或者先使用slice复制数组，然后执行splice。

我个人很喜欢filter，因为它简单易懂，意图明确

过滤器

function removeItem(array, n) {
  return array.filter((elem, i) => i !== n);
}

const original = [1,2,3,4];

console.log(removeItem(original, 1));
console.log(original);

减少

function removeItem (array, n) {
  return array.reduce((result, elem, i) => {
    if (i !== n) result.push(elem);
    return result;
  }, [])
}

const original = [1,2,3,4];

console.log(removeItem(original, 1));
console.log(original);

切片和接合

function removeItem(array, n) {
  const result = array.slice();
  result.splice(n, 1);
  return result;
}

const original = [1,2,3,4];

console.log(removeItem(original, 1));
console.log(original);

性能测试

https://jsperf.com/so53833297

文档

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

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

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

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

Answer 2

function removeItem(array, n) {
    return array.filter((x, i) => i != n)
}

Answer 3

var array = [2,1,3,5,6,8,9,7];
function removeArray(array,n){
    array.splice(array.indexOf(n),1);
    return array;
}

console.log(array);
array = removeArray(array, 6);
console.log(array);