Question

我正在尝试使用递归数组（plunk：http://plnkr.co/edit/3npsad?p=preview）递归加载Angular 2组件。

给定这个递归数组：

[
  {
    "id": 1,
    "text": "abc"
  },
  {
    "id": 2,
    "text": "def",
    items: [
      {
        "id": 21,
        "text": "def-1",
        items: [
          {
            "id": 211,
            "text": "def-1-1"
          },
          {
            "id": 212,
            "text": "def-1-2"
          }
        ]
      },
      {
        "id": 22,
        "text": "def-2"
      }
    ]
  }
]

我需要以下输出：

<my-item>
    <div id="1" text="abc"></div>
</my-item>
<my-item>
    <div id="2" text="def"></div>
    <my-item>
        <div id="21" text="def-1"></div>
        <my-item>
            <div id="211" text="def-1-1"></div>
        </my-item>
        <my-item>
            <div id="212" text="def-1-2"></div>
        </my-item>
    </my-item>
    <my-item>
        <div id="22" text="def-2"></div>
    </my-item>
</my-item>

我只能在插件中显示第一级输入。如何使我的组件递归迭代以呈现所需的输出？输入数组可以包含任意数量的元素和嵌套。

谢谢！

Answer 1

我会以这种方式创建你的组件：

@Component({
  selector: 'my-item',
  template: `
    <div id="data.id" text="data.def"></div>
    <my-item *ngFor="let item of items" [data]="item"></my-item>
  `
})
export class MyItemComponent {
  @Input() data: any;
}

并将其称为来自其他组件的组件并提供整个组件数据：

@Component({
  selector: 'other-comp',
  template: `
    <my-item [data]="data" *ngFor="let data of wholeData"></my-item>
  `
})
export class OtherComponent {
  wholeData = [
    {
      "id": 1,
      "text": "abc"
    },
    (...)
  ];
}

Answer 2

<强>更新

引入@NgModule后，不再需要将directives迁移到@NgModule forwardRef。

<强>原始

<my-item *ngFor="let itm of items" [id]="itm.id" [text]="itm.text" [items]="itm.items" >
</my-item>

@Component({
  selector: 'my-item',
  styles: ['div {padding-left: 32px;}']
  providers: [],
  template: `<div>{{id}} - {{text}}
    <my-item *ngFor="let itm of items" [id]="itm.id" [text]="itm.text" [items]="itm.items" >
    </my-item>
    </div>

  `,
  directives: [forwardRef(()=> ItemComponent)]
})
export class ItemComponent {
  @Input() id: string;
  @Input() text: string;
  @Input() items: any[];
  constructor() {
  }
}

forwardRef是必需的，因为在声明类ItemComponent之前会引用它。

Plunker example

Answer 3

这是让你开始的东西。您需要自己实现HTML返回功能：

  var a = [
  {
    "id": 1,
    "text": "abc"
  },
  {
    "id": 2,
    "text": "def",
    items: [
      {
        "id": 21,
        "text": "def-1",
        items: [
          {
            "id": 211,
            "text": "def-1-1"
          },
          {
            "id": 212,
            "text": "def-1-2"
          }
        ]
      },
      {
        "id": 22,
        "text": "def-2"
      }
    ]
  }
];

function iterateRecursive(array) {
    for(var i = 0; i < array.length; i++) {
    if(array[i].items) {
        console.log(array[i].text);
      //uncomment: printHtml(array[i].id, array[i].text);
        iterateRecursive(array[i].items)
    } else {    
        console.log(array[i].text);         
    }

  }
}


iterateRecursive(a);

//implement this function that takes an id and text and returns html
//call it in place of console log
function printHtml(id, text) {

}

使用递归数组加载递归组件

3 个答案: