具有相同键的数组的Javascript连接值

Question

我正在尝试合并以下对象：

var permission = { 
  'id': '94cabc1f-d4d3-430d-b41d-ebfb1bd94f27',
  'user_id': '7aaac6d2-7316-4e3a-a53f-81b4aa0a14a1',
  'permissions': { 
        devices: [ 'read' ], 
        reports: [ 'read' ] 
    }
}

var newPermission = { 
  devices: [ 'update' ]
}

我的结果应该如下所示：

{ 
  'id': '94cabc1f-d4d3-430d-b41d-ebfb1bd94f27',
  'user_id': '7aaac6d2-7316-4e3a-a53f-81b4aa0a14a1',
  'permissions': { 
        devices: [ 'read','update' ], 
        reports: [ 'read' ] 
    }
}

我使用了Object.assign，它没有附加到权限，有没有办法做到这一点。我是 ES6 新手。

Answer 1

var permission = { 'id': '94cabc1f-d4d3-430d-b41d-ebfb1bd94f27', 'user_id': '7aaac6d2-7316-4e3a-a53f-81b4aa0a14a1', 'permissions': { devices: [ 'read' ], reports: [ 'read' ] }};

var newPermission = { devices: [ 'update' ]};

// if you have more number of items in newPermission array like ['update', 'update1', 'update2'], below logic will add all of them after `read`.

newPermission.devices.forEach((item)=>{
   permission.permissions.devices.push(item);
})

console.log(permission);

Answer 2

如何取 entries 的 Object 然后使用 reduce 对它们进行分组。像这样的：

var permission = { 
  'id': '94cabc1f-d4d3-430d-b41d-ebfb1bd94f27',
  'user_id': '7aaac6d2-7316-4e3a-a53f-81b4aa0a14a1',
  'permissions': { 
        devices: [ 'read' ], 
        reports: [ 'read' ] 
    }
};

var newPermission = { 
  devices: [ 'update' ],
  reports:['delete']
};

permission.permissions = Object.entries(newPermission).reduce((a, [key, arr])=>{
    a[key] = [...arr, ...permission.permissions[key]] ;
    return a;
},{});

console.log(permission)

Answer 3

你可以这样做：

var permission = { 
  'id': '94cabc1f-d4d3-430d-b41d-ebfb1bd94f27',
  'user_id': '7aaac6d2-7316-4e3a-a53f-81b4aa0a14a1',
  'permissions': { 
        devices: [ 'read' ], 
        reports: [ 'read' ] 
    }
}

var newPermission = { 
  devices: [ 'update' ]
}

var permissions = permission['permissions'];

for(var key in permissions){
 for(var key2 in newPermission){
   if(key === key2){
    permissions[key] = [...permissions[key], ...newPermission[key]]
   }
 }
}
console.log(permission)

Answer 4

我使用了扩展运算符，就像 Object.assign()。你可以在这里阅读https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Spread_syntax

const permission = { 
  'id': '94cabc1f-d4d3-430d-b41d-ebfb1bd94f27',
  'user_id': '7aaac6d2-7316-4e3a-a53f-81b4aa0a14a1',
  'permissions': { devices: [ 'read' ], reports: [ 'read' ] }
}

const newPermission = { 
  devices: [ 'update' ]
}

const result = {
  ...permission, // Here we copy the main object permission
  permissions: { // Change the field permissions
    ...permission.permissions, // Copy permissions that do not delete reports and other fields
    devices: [ // Merge two arrays
      ...permission.permissions.devices,
      ...newPermission.devices
    ]
  }
}

console.log(result)

Answer 5

var permission = { 
  'id': '94cabc1f-d4d3-430d-b41d-ebfb1bd94f27',
  'user_id': '7aaac6d2-7316-4e3a-a53f-81b4aa0a14a1',
  'permissions': { 
        devices: [ 'read' ], 
        reports: [ 'read' ] 
    }
}

var newPermission = { 
  devices: [ 'update' ],
  reports: [ 'write' ] 
}


var result = Object.fromEntries(
  Object.entries(permission.permissions).map(([key, value]) => {
    if (Object.keys(newPermission).includes(key)) {
      value.push(...newPermission[key]);
    }
    return [key, value];
  })
);

permission.permissions = result;

console.log(permission);

Answer 6

如果你想避免使用嵌套循环，这里是使用 Map 的不同方法

 var permission = { 'id': '94cabc1f-d4d3-430d-b41d-ebfb1bd94f27', 'user_id': '7aaac6d2-7316-4e3a-a53f-81b4aa0a14a1', 'permissions': { devices: [ 'read' ], reports: [ 'read' ] } }     
    var newPermission = { 
      devices: [ 'update' ]
    }
    map=new Map()
    Object.entries(permission.permissions).map(o=>map.set(o[0],o[1]))
         for(let key in newPermission){
          upd = map.get(key)
           if(upd) upd.push(...newPermission[key])
         }
    
    console.log(permission)