如何将对象的结构转换为另一种结构？ JavaScript

Question

我有这个 JS 对象的结构：

 const obj1 = {
      "groups": [
        {
          "name": "test",
          "type": "app"
        },
        {
          "name": "test2",
          "type": "app"
        },
        {
          "name": "test1",
          "type": "app2"
        },
        {
          "name": "test3",
          "type": "app2"
        }
      ]
    }

我需要最终得到这个： 结果：

 const obj1 = {
      app: {groups: [{name: 'test'},{name: 'test2'}]},
      app2: {groups: [{name: 'test1'},{name: 'test3'}]},
    }

可能是 ES6+ 方法或更旧

Answer 1

这归结为只是通过obj1.groups迭代构建一个新的输出对象：

 const obj1 = { "groups": [ { "name": "test", "type": "app" }, { "name": "test2", "type": "app" }, { "name": "test1", "type": "app2" }, { "name": "test3", "type": "app2" } ] }; const out = {}; for (let group of obj1.groups) { out[group.type] = out[group.type] || { groups: [] }; out[group.type].groups.push({ name: group.name }); } console.log(out);

或者，您可以使用Array.reduce()将其包装成单个表达式：

 const obj1 = { "groups": [ { "name": "test", "type": "app" }, { "name": "test2", "type": "app" }, { "name": "test1", "type": "app2" }, { "name": "test3", "type": "app2" } ] }; const out = obj1.groups.reduce((out, group) => { out[group.type] = out[group.type] || { groups: [] }; out[group.type].groups.push({ name: group.name }); return out; }, {}); console.log(out);

Answer 2

您可以使用Array.reduce()简洁地做到这一点：

 const obj1 = { "groups": [{ "name": "test", "type": "app" }, { "name": "test2", "type": "app" }, { "name": "test1", "type": "app2" }, { "name": "test3", "type": "app2" }] }; const result = obj1.groups.reduce((obj, { name, type }) => { return (obj[type].groups.push({ name }), obj); }, { app: { groups: [] }, app2: { groups: [] } }); console.log(result);

或者使用扩展运算符：

 const obj1 = { "groups": [{ "name": "test", "type": "app" }, { "name": "test2", "type": "app" }, { "name": "test1", "type": "app2" }, { "name": "test3", "type": "app2" }] }; const result = obj1.groups.reduce((o, { name, type }) => ({ ...o, [type]: { groups: [...((o[type] || {}).groups || []), { name }] } }), {}); console.log(result);