Question

我有一个这样的对象数组

array = {
    "microservices": [
        {
            "id": 1,
            "permissions": [
                {
                    "id": 65,
                    "name": "Default permission"
                },
                {
                    "id": 64,
                    "name": "Super user Access"
                }
            ]
        },
        {
            "id": 2,
            "permissions": []
        },
        {
            "id": 3,
            "permissions": [
                {
                    "id": 18,
                    "name": "Script: Update"
                },
                {
                    "id": 15,
                    "name": "Application: Delete"
                },
                {
                    "id": 9,
                    "name": "Workspace: Create"
                }
            ]
        }
    ]
}

从微服务数组中，我只想获取“权限”数组并将其存储到一个新变量中，我进行了搜索，但没有任何相关的解决方案，在此先感谢

Answer 1

您可以使用map运算符并单独获取该特定属性。请检查下面的JS示例。

const array = {
  "microservices": [{
      "id": 1,
      "permissions": [{
          "id": 65,
          "name": "Default permission"
        },
        {
          "id": 64,
          "name": "Super user Access"
        }
      ]
    },
    {
      "id": 2,
      "permissions": []
    },
    {
      "id": 3,
      "permissions": [{
          "id": 18,
          "name": "Script: Update"
        },
        {
          "id": 15,
          "name": "Application: Delete"
        },
        {
          "id": 9,
          "name": "Workspace: Create"
        }
      ]
    }
  ]
}
const output = []
array.microservices.map(function(x) {
  output.push(...x.permissions);
})
console.log(output);

Answer 2

仅需按以下步骤迭代json对象。新数组“权限”将返回您的数据。

 getPermissions(){
   this.array.microservices.forEach(element => {
    element.permissions.forEach(ele => {
      this.permissions.push(ele);
     });
   });

   console.log(this.permissions);       
 }

预先也可以使用.map运算符。

Answer 3

这不是特定的Angular或Typescript问题，但是您可以这样做

const whatYouNeed = array.microservices.reduce((sum, item) => {
    sum.push(item.permissions);
    return sum;
}, []);

或者如果您希望它是一个级别：

const whatYouNeed = array.microservices.reduce((sum, item) => {
    sum = sum.concat(item.permissions);
    return sum;
}, []);

Answer 4

由于您想要一个包含所有权限的数组，因此这是最干净的方法。了解flatMap here

 const permissions = array.microservices.flatMap(i => i.permissions)     
 console.log(permissions);

使用polyfill获得浏览器支持。在上面的链接中可用。

Answer 5

您可以使用ES6 map。

const permissionsArrays = array.microservices.map(microservice => microservice.permissions)

Answer 6

因此，假设这是您收到的json数据：

{
  "microservices": [
    {
      "id": 1,
      "permissions": [
        {
          "id": 65,
          "name": "Default permission"
        },
        {
          "id": 64,
          "name": "Super user Access"
        }
      ]
    },
    {
      "id": 2,
      "permissions": []
    },
      {
      "id": 3,
      "permissions": [
        {
          "id": 18,
          "name": "Script: Update"
        },
        {
          "id": 15,
          "name": "Application: Delete"
        },
        {
          "id": 9,
          "name": "Workspace: Create"
        }
      ]
    }
   ]
 }

只需创建一个界面即可使用智能感知：

export interface Microservice {
  microservices?: (MicroservicesEntity)[] | null;
}
export interface MicroservicesEntity {
  id: number;
  permissions?: (PermissionsEntity | null)[] | null;
}
export interface PermissionsEntity {
  id: number;
  name: string;
}

通过这种方式，您可以获得智能感知的帮助，因此可以通过引用json数据的接口来访问数据：

data: Microservice;

之后，使用地图获取权限数组

Answer 7

首先，您有一个包含数组而不是实际数组的对象。但是让我们暂时忽略它。

array =  {
  "microservices": [
    {
      "id": 1,
      "permissions": [
        {
          "id": 65,
          "name": "Default permission"
        },
        {
          "id": 64,
          "name": "Super user Access"
        }
      ]
    },
    {
      "id": 2,
      "permissions": []
    },
      {
      "id": 3,
      "permissions": [
        {
          "id": 18,
          "name": "Script: Update"
        },
        {
          "id": 15,
          "name": "Application: Delete"
        },
        {
          "id": 9,
          "name": "Workspace: Create"
        }
      ]
    }
   ]
 }


const permissions = array.microservices.map(item => {
    return item.permissions;
});

如何从数组对象中的嵌套数组获取数据

7 个答案: