Angular 2,传递完整对象作为参数

Question

我研究角2,我有问题.

实际上,实际上,我将每个组件属性传递给模板,如下所示:

import {Component, bootstrap, NgFor,NgModel} from 'angular2/angular2';
import {TodoItem} from '../item/todoItem';


@Component({
  selector: 'todo-list',
  providers: [],
  templateUrl: 'app/todo/list/todoList.html',
  directives: [NgFor,TodoItem,NgModel],
  pipes: [],
  styleUrls:['app/todo/list/todoList.css']
})
export class TodoList {

  list:Array<Object>;

  constructor(){
    this.list = [
      {title:"Text 1", state:false},
      {title:"Text 2", state:true}
    ];
  }
}



<todo-item [title]="item.title" [state]="item.state" *ng-for="#item of list"></todo-item>

import {Component, bootstrap, Input} from 'angular2/angular2';


@Component({
  selector: 'todo-item',
  providers: [],
  templateUrl: 'app/todo/item/todoItem.html',
  directives: [],
  pipes: [],
  styleUrls:['app/todo/item/todoItem.css']
})
export class TodoItem {

  @Input()
  title:String;

  @Input()
  state:Boolean;


}

我想知道我是否可以通过传递每个属性直接传递模板内的完整对象？

<todo-item [fullObj]="item" *ng-for="#item of list"></todo-item>

Answer 1

是的,将整个对象作为属性传递是完全正确的.

语法是相同的,所以只需为整个对象创建一个属性.

@Component({
  selector: 'my-component'
})
export class MyComponent{
  @Input() item;
}
<my-component [item]=item></my-component>

这是一个例子:http://www.syntaxsuccess.com/viewarticle/recursive-treeview-in-angular-2.0

Answer 2

这样做没有问题.您可以选择以下两种语法:

@Component({
    selector: 'my-component',
    inputs: ['item: item']
})
export class TodoItem {
    item: { title: string, state: boolean };
}

要么

@Component({
    selector: 'my-component'
})
export class TodoItem {
    @Input() item: { title: string, state: boolean };
}

和绑定:

<todo-item [item]="item" *ng-for="#item of list"></todo-item>

但是,您需要注意的是,当以这种方式传递对象时,您将传递对该对象的引用.这意味着您对"child"组件中的对象所做的任何更改都将反映在"父"Component对象中:

export class TodoItem implements OnInit {

    ngOnInit() {
        //This is modifying the object in "parent" Component,
        //as "this.item" holds a reference to the same "parent" object
        this.item.title = "Modified title";
    }

}

例外情况是,如果您指定了其他对象.在这种情况下,它不会反映在"父"组件中,因为它不再是相同的对象引用:

export class TodoItem implements OnInit {

    ngOnInit() {
        //This will not modify the object in "parent" Component,
        //as "this.item" is no longer holding the same object reference as the parent
        this.item = {
            title: 'My new title',
            state: false
        };
    }

}