Question

我对Javascript很新，而且映射有点令人困惑，需要一些帮助。我有一个对象数组的记录集，每个对象具有相同的名称，但对象中的其他3个元素是不同的。该数组看起来像这样

[ { Name: 'MyGroupName',
    App_Name: 'App Name 1',
    App_ID: '1',
    App_Members: 32 },
  { Name: 'MyGroupName',
    CI_Name: 'App Name 2',
    Apps_ID: '2',
    App_Members: 96 },
  { Name: 'MyGroupName',
    CI_Name: 'App Name 3',
    Apps_ID: '2',
    App_Members: 348 }
]

我希望使用名称将他们组合在一起，所以当在屏幕上显示时，我不会反复重复这个名字。所以我需要让我的返回数组看起来像这样

let example = {
'MyGroupName': [
    { 
      App_Name: 'App Name 1',
      App_ID: '1',
      App_Members: 32 
    },
    { 
      CI_Name: 'App Name 2',
      Apps_ID: '2',
      App_Members: 96 
    },
    { 
      CI_Name: 'App Name 3',
      Apps_ID: '2',
      App_Members: 348 
    }
  ]

我已经开始使用下面的代码，但是我碰到了一堵砖墙而且让我很困惑，任何帮助都会受到赞赏。

.then(function (recordSet) {
   let groupToArrayOfApps = {}

   for(let record in recordSet) {
       // todo: add group name as key to the map & app name to array of apps
    }

Answer 1

您可以使用对象作为结果，并删除对象副本中的属性Name。

var data = [{ Name: 'MyGroupName', App_Name: 'App Name 1', App_ID: '1', App_Members: 32 }, { Name: 'MyGroupName', CI_Name: 'App Name 2', Apps_ID: '2', App_Members: 96 }, { Name: 'MyGroupName', CI_Name: 'App Name 3', Apps_ID: '2', App_Members: 348 }],
    grouped = Object.create(null);

data.forEach(function (a) {
    var o = Object.assign({}, a);
    delete o.Name;
    grouped[a.Name] = grouped[a.Name] || [];
    grouped[a.Name].push(o);
});

console.log(grouped);

如果您不介意改变原始对象，可以使用不复制属性的版本，只删除不需要的属性Name。

var data = [{ Name: 'MyGroupName', App_Name: 'App Name 1', App_ID: '1', App_Members: 32 }, { Name: 'MyGroupName', CI_Name: 'App Name 2', Apps_ID: '2', App_Members: 96 }, { Name: 'MyGroupName', CI_Name: 'App Name 3', Apps_ID: '2', App_Members: 348 }],
    grouped = Object.create(null);

data.forEach(function (a) {
    grouped[a.Name] = grouped[a.Name] || [];
    grouped[a.Name].push(a);
    delete a.Name;
});

console.log(grouped);

Answer 2

现在您只需要检查record.Name

中是否已存在groupToArrayOfApps作为属性

let recordSet = [ { Name: 'MyGroupName',
    App_Name: 'App Name 1',
    App_ID: '1',
    App_Members: 32 },
  { Name: 'MyGroupName',
    CI_Name: 'App Name 2',
    Apps_ID: '2',
    App_Members: 96 },
  { Name: 'MyGroupName',
    CI_Name: 'App Name 3',
    Apps_ID: '2',
    App_Members: 348 }
];

let groupToArrayOfApps = {};

recordSet.forEach(function(record){
  // Check if property already exists, if not add it as empty array
  if(!groupToArrayOfApps[record.Name]) groupToArrayOfApps[record.Name] = [];
  // Prepare the record to be added (without Name property)
  let addRecord = Object.assign({}, record);
  // Add the desired record to the property array
  groupToArrayOfApps[record.Name].push(addRecord);
});

console.log(groupToArrayOfApps);

Javascript映射问题

2 个答案: