js中concat的实现

let newArray = array1.concat(array2, array3, ..., arrayX);

Array.prototype.myConcat = function(...args) {
  let result = [];
  for (let i = 0; i < this.length; i++) {
    result.push(this[i]);
  }
  for (let i = 0; i < args.length; i++) {
    if (Array.isArray(args[i])) {
      for (let j = 0; j < args[i].length; j++) {
        result.push(args[i][j]);
      }
    } else {
      result.push(args[i]);
    }
  }
  return result;
};

function deepConcat(arrays) {
  return arrays.reduce((acc, val) => acc.concat(Array.isArray(val) ? deepConcat(val) : val), []);
}

let arr1 = [1, 2, 3];
let arr2 = [4, 5, 6];
let arr3 = [7, 8];

let combinedArray = arr1.concat(arr2, arr3);
console.log(combinedArray); // 输出: [1, 2, 3, 4, 5, 6, 7, 8]

// 使用自定义的 myConcat 方法
Array.prototype.myConcat = function(...args) {
  let result = [];
  for (let i = 0; i < this.length; i++) {
    result.push(this[i]);
  }
  for (let i = 0; i < args.length; i++) {
    if (Array.isArray(args[i])) {
      for (let j = 0; j < args[i].length; j++) {
        result.push(args[i][j]);
      }
    } else {
      result.push(args[i]);
    }
  }
  return result;
};

let customCombinedArray = arr1.myConcat(arr2, arr3);
console.log(customCombinedArray); // 输出: [1, 2, 3, 4, 5, 6, 7, 8]