此解决方案适用于任何深度级别（指定嵌套数组结构的深度）的数组。

function flatten(obj) {
    var out = [];
    function cleanElements(input) {
        for (var i  in input){
            if (input[i]instanceof Array){
                cleanElements(input[i]);
            }
            else {
                out.push(input[i]);
            }
        }
    }
    cleanElements(obj);
    return (out);
}

以下代码将压平深度嵌套的数组：

/**
 * [Function to flatten deeply nested array]
 * @param  {[type]} arr          [The array to be flattened]
 * @param  {[type]} flattenedArr [The flattened array]
 * @return {[type]}              [The flattened array]
 */
function flattenDeepArray(arr, flattenedArr) {
  let length = arr.length;

  for(let i = 0; i < length; i++) {
    if(Array.isArray(arr[i])) {
      flattenDeepArray(arr[i], flattenedArr);
    } else {
      flattenedArr.push(arr[i]);
    }
  }

  return flattenedArr;
}

let arr = [1, 2, [3, 4, 5], [6, 7]];

console.log(arr, '=>', flattenDeepArray(arr, [])); // [ 1, 2, [ 3, 4, 5 ], [ 6, 7 ] ] '=>' [ 1, 2, 3, 4, 5, 6, 7 ]

arr = [1, 2, [3, 4], [5, 6, [7, 8, [9, 10]]]];

console.log(arr, '=>', flattenDeepArray(arr, [])); // [ 1, 2, [ 3, 4 ], [ 5, 6, [ 7, 8, [Object] ] ] ] '=>' [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 ]

ES6的纯粹魔力

const flat = A => A.reduce((A, a) => Array.isArray(a) ? [...A, ...flat(a)] : [...A, a], []);

以下是使用堆栈的非递归展平深度的解决方案。

    function flatten(input) {
        const stack = [...input];
        const res = [];
        while (stack.length) {
            const next = stack.pop();
            if (Array.isArray(next)) {
                stack.push(...next);
            } else {
                res.push(next);
            }
        }
        return res.reverse();
    }
    const arrays = [["$6"], ["$12"], ["$25"], ["$25"], ["$18"], ["$22"], ["$10"]];
    flatten(arrays);

你可以使用Ramda JS flatten

var arr=[[1,2]，[3]，[4,5]]；var flattedArray=R.flatten（arr）；console.log（flattedArray）<script src=“https://cdnjs.cloudflare.com/ajax/libs/ramda/0.25.0/ramda.js“></script>

由于ES2019引入了flat和flatMap，因此任何阵列都可以这样做：

const myArr = [["$6"], ["$12"], ["$25"], ["$25"], ["$18"], ["$22"], ["$10"]]
const myArrFlat= myArr.flat(Infinity);
console.log(myArrFlat); // ["$6", "$12", "$25", ...]

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