Javascript-使用映射或过滤器基于值的存在返回数组成员的子集

我已经对此进行了研究，虽然有很多关于这些概念的信息，但我很难理解如何将所有这些想法结合起来以解决我的问题

我有一个数组：

[
  {
    route: ["", "scheduler"],
    name: "scheduler",
    settings: {
      icon: "user",
      auth: true,
      roles: ["Employee", "Admin"],
      pos: "left"
    },
    moduleId: PLATFORM.moduleName("../components/scheduler/scheduler"),
    nav: true,
    title: "scheduler"
  },
  {
    route: "jobs",
    name: "jobs",
    moduleId: PLATFORM.moduleName("../components/jobs/jobsList"),
    settings: {
      icon: "list",
      auth: true,
      roles: ["Employee"],
      pos: "left"
    },
    nav: true,
    title: "Jobs"
  },
  {
    route: "clients",
    name: "clients",
    moduleId: PLATFORM.moduleName("../components/clients/clientList/clientList"),
    title: "Clients",
    nav: true,
    settings: {
      nav: [
        {
          icon: "list",
          route: "clients/ClientsList",
          name: "clientList",
          moduleId: PLATFORM.moduleName(
            "../components/clients/clientList/clientList"
          ),
          href: "#clients/clientsList",
          title: "Client List",
          roles: ["Employee", "Admin"]
        },
        {
          icon: "user",
          route: "clients/create",
          name: "aboutTeam",
          moduleId: PLATFORM.moduleName(
            "../components/clients/clientCreate/clientCreate"
          ),
          href: "#clients/Create",
          title: "Create Client",
          roles: ["Employee", "Admin"]
        }
      ],
      icon: "user",
      auth: true,
      roles: ["Employee", "Admin"],
      pos: "left"
    }
  },
  {
    route: "clients/ClientsList",
    name: "clientList",
    moduleId: PLATFORM.moduleName("../components/clients/clientList/clientList"),
    settings: {
      icon: "list",
      auth: true,
      roles: ["Employee", "Admin"],
      pos: "left"
    }
  },
  {
    route: "clients/create",
    name: "aboutTeam",
    moduleId: PLATFORM.moduleName("../components/clients/clientCreate/clientCreate"),
    settings: {
      icon: "user",
      auth: true,
      roles: ["Employee", "Admin"],
      pos: "left"
    }
  },
  {
    route: "companyDetail",
    name: "companyDetail",
    moduleId: PLATFORM.moduleName("../components/administration/companyDetail/companyDetail"),
    settings: {
      icon: "list",
      auth: true,
      roles: ["Employee", "Admin"],
      pos: "left"
    },
    nav: true,
    title: "Company Detail"
  },
  {
    route: "user",
    name: "user",
    moduleId: PLATFORM.moduleName("../components/administration/user/user"),
    settings: {
      icon: "user",
      auth: true,
      roles: ["Employee", "Admin"],
      pos: "right"
    },
    nav: true,
    title: "User"
  },
  {
    route: "notFound",
    name: "notFound",
    settings: { auth: false },
    moduleId: PLATFORM.moduleName("../components/notFound/notFound"),
    nav: false,
    title: "Not Found"
  }
]

每个都有一个设置选项，其中有一个角色数组

我想循环检查每个数组成员，比如说，该成员是否担任“Admin”角色，然后使用“push”将其添加到新数组中

然而，我希望学习JavaScript并扩展我的知识。我想我应该使用“map”选项和“fat arrow”函数来简化代码，这样我就有了一个新的数组，其中包含了所有项目，其中角色包含一个userRole of admin

这是我的尝试：

console.log(this.menu.map(r => r.filter(f => f.settings.roles === userRole)));

完整的功能是

public userMenu(userName: string, userRole: string): any {
const fullMenu = this.menuList();
console.log("userRole: ", userRole);
console.log(this.menu.map(r => r.filter(f => f.settings.roles === userRole)));
}

“userRole”存在并显示在控制台中，但我收到以下错误：

未捕获的TypeError:无法读取未定义的属性“map”

如何构造map函数以使其工作，从而只返回上面较大数组中角色数组中包含“Admin”的项目

我想循环检查每个数组成员，比如说，该成员是否担任“Admin”角色，然后使用“push”将其添加到新数组中

函数返回新数组，因此您无需自己创建新数组。如果需要在数组中循环，请改用

forEach

未捕获的TypeError:无法读取未定义的属性“map”

请显示设置此菜单的代码。

log（this.menu.map（r=>r.filter（f=>f.settings.roles===userRole））；

• map

  ，

  filter

  ，

  reduce

  只能与数组一起使用。上面的代码显示，您对对象

  r

  使用

  filter

  （正如

  菜单

  是一个对象数组）

• f.settings.roles===userRole

  ：userRole是字符串，而settings.roles是数组，因此您必须使用

  包含
  （或
  索引of
  ）作为筛选条件
  

因为您只想筛选满足条件的项，所以使用

filter

就足够了，如下所示

menu.filter（r=>r.settings.roles&&r.settings.roles.includes（'Admin'））

似乎未定义

此.menu

-是什么设置了

此.menu

？