如何在JavaScript中过滤和循环嵌套的关联对象？

Question

所以我总共有三个嵌套的关联对象/数组。首先制作Employee1和employee2，然后创建员工以嵌套两个关联对象。接下来，我创建了第三个关联对象employee3，以嵌套到employees对象中。我现在要做的是使用.filter（）方法过滤2D数组，只调出当前在那里工作的员工，这在数组中用[“isCurrent”] = true表示;但我在控制台窗口中得到的所有内容都是未定义的。为什么会发生这种情况，我该如何解决这个问题？

var employee1 = [];
employee1["id"] = 33;
employee1["name"] = "Carey Shanks";
employee1["title"] = "Knife Maker";
employee1["department"] = "fabrication";
employee1["isCurrent"] = true;

var employee2 = [];
employee2["id"] = 34;
employee2["name"] = "Giles Newman";
employee2["title"] = "Lead Sales";
employee2["department"] = "Customer Service";
employee2["isCurrent"] = true;

var employees = [];
employees[0] = [];
employees[0]["id"] = 33;
employees[0]["name"] = "Carey Shanks";
employees[0]["title"] = "Knife Maker";
employees[0]["department"] = "fabrication";
employees[0]["isCurrent"] = true;

var employee3 = [];
employee3["id"] = 35;
employee3["name"] = "Tori G.";
employee3["title"] = "Product Demonstrator";
employee3["department"] = "Marketing";
employee3["isCurrent"] = false;

//MERING THE ARRAYS
employees.push(employee2);
employees.push(employee3);

//TESTING TO SEE IF IT POPULATED
//window.console.log(employees);

var i;
var currentEmployee = function (isCurrent) {
    var isCurrentEmployee = true;
    for (i in employees) {
        if (isCurrent !== true) {
            isCurrentEmployee = false;
            break;
        }
    }
    return isCurrentEmployee;
};
var isCompanyEmployee = employees.filter(currentEmployee);

window.console.log(isCompanyEmployee[i]);

Answer 1

一些问题：

• 数组只能与数字指示一起使用。如果要使用任意字符串键，请改用对象。
• filter回调的第一个参数是迭代的当前项;您的 var currentEmployee = function (isCurrent) { 将isCurrent定义为第一个参数，但这不是isCurrent属性。如果您想立即从对象中提取isCurrent属性，请改为对该参数进行解构，然后您可以返回它：

  var currentEmployee = function ({ isCurrent }) {
    return isCurrent;
  }

  或者，如果你对解构不满意，这相当于

  var currentEmployee = function (employee) {
    return employee.isCurrent;
  }

• i在currentEmployee函数之外没有任何意义 - 记录过滤后的数组： console.log(isCompanyEmployee);
• 你永远不会把employee1推到阵列。

var employee1 = {};
employee1["id"] = 33;
employee1["name"] = "Carey Shanks";
employee1["title"] = "Knife Maker";
employee1["department"] = "fabrication";
employee1["isCurrent"] = true;

var employee2 = {};
employee2["id"] = 34;
employee2["name"] = "Giles Newman";
employee2["title"] = "Lead Sales";
employee2["department"] = "Customer Service";
employee2["isCurrent"] = true;

var employees = [];
employees[0] = {};
employees[0]["id"] = 33;
employees[0]["name"] = "Carey Shanks";
employees[0]["title"] = "Knife Maker";
employees[0]["department"] = "fabrication";
employees[0]["isCurrent"] = true;

var employee3 = {};
employee3["id"] = 35;
employee3["name"] = "Tori G.";
employee3["title"] = "Product Demonstrator";
employee3["department"] = "Marketing";
employee3["isCurrent"] = false;

//MERING THE ARRAYS
employees.push(employee1);
employees.push(employee2);
employees.push(employee3);

//TESTING TO SEE IF IT POPULATED
//window.console.log(employees);

var i;
var currentEmployee = function ({ isCurrent }) {
    return isCurrent;
};
var currentEmployees = employees.filter(currentEmployee);

window.console.log(currentEmployees);