是否可以抽象出模板的公共部分？

Question

例如，我有多个用于分页集合的组件。模板示例：

<div *ngIf="!isFormVisible">
    <button class="btn" [ngClass]="{'btn-info': filtered, 'btn-default': !filtered}" (click)="showForm()">Filter</button>
    <button class="btn btn-default" (click)="createNew()">Create new</button>
</div>

<div class="panel panel-default" *ngIf="isFormVisible">
    <div class="panel-heading">
        <h3 class="panel-title">Filter<button type="button" class="close" (click)="hideForm()">&times;</button></h3>
    </div>
    <div class="panel-body form-horizontal">
        <form (ngSubmit)="onFormSubmit()">
            <fieldset>
                <div class="form-group">
                    <label class="control-label col-md-2" for="id">Id</label>
                    <div class="controls col-md-10">
                        <input type="text" class="form-control [(ngModel)]="filter.id"/>
                    </div>
                </div>

                <div class="form-group">
                    <label class="control-label col-md-2" for="userName">Username</label>
                    <div class="controls col-md-10">
                        <input type="text" class="form-control" [(ngModel)]="filter.userName"/>
                    </div>
                </div>

                <div class="form-group">
                    <div class="col-md-offset-2 col-md-10">
                        <button type="submit" class="btn btn-default">Filter</button>
                        <button type="reset" class="btn btn-default" (click)="onFormReset()">Reset</button>
                    </div>
                </div>
            </fieldset>
        </form>
    </div>
</div>

<div *ngIf="busy">
    <h1><i class="fa fa-spinner fa-spin fa-pull-left"></i> Loading...</h1>
</div>

<label *ngIf="!currentQuery.result?.length && !busy">No results</label>
<div class="table-responsive" *ngIf="currentQuery.result?.length && !busy">
    <table class="table table-striped table-hover">
        <thead>
            <tr>
                <th>
                    <a href="javascript:void(0);" (click)="sortBy('id')">Id</a>
                </th>
                <th>
                    <a href="javascript:void(0);" (click)="sortBy('userName')">Username</a>
                </th>
                <th></th>
            </tr>
        </thead>
        <tbody>
            <tr *ngFor="#user of currentQuery.result">
                <td>{{user.id}}</td>
                <td>{{user.userName}}</td>
                <td><button class="btn btn-default btn-xs" (click)="manageUser(user.id)">Manage</button></td>
            </tr>
        </tbody>
    </table>
</div>
<pagination [currentPage]="currentQuery.pageIndex" [totalPages]="currentQuery.totalPages" (onPageClick)="onPageClick($event)"></pagination>

对于特定组件，我只对过滤输入字段、表头和行模板感兴趣。对所有组件重复所有其余部分。是否有可能以某种方式将 DRY 原则应用于模板并抽象出重复部分？

Answer 1

您可以添加<ng-content>进行转入。

@Component({
  selector: 'reuse-cmp',
  ...
  template: `
<div>some fixed content</div>
  <ng-content></ng-content>
<div>some fixed content in the middle</div>
  <ng-content select=".below"></ng-content>
<div>some fixed content below</div>
`
})
class ReusablePart {}

然后像这样使用它

<reuse-cmp>
  <other-dynamic-content class="below"></other-dynamic-content>
  <dynamic-content></dynamic-content>
</resue-cmp>

Transclusion 将所有具有类below 的顶级元素放置在此标记为<ng-content select=".below"></ng-content> 的位置，其余与放置<ng-content></ng-content> 的特定选择器不匹配的位置。

Answer 2

如果您需要将其他部分作为输入，您可以为这些不同的部分创建组件并利用 ng-content。

这是一个示例：

@Component({
  selector: 'test'
  template: `
    <div>
      <ng-content></ng-content>
    </div>
  `
})
export class TestComponent {
}

您可以在另一个组件中以这种方式使用此组件：

<test>
  <div>
    Part to include in the test component template (see ng-content)
  </div>
</test>

在你的情况下，它可能是这样的：

<pageLayout>
  <form (ngSubmit)="onFormSubmit()">
    <fieldset>
      <div class="form-group">
        <label class="control-label col-md-2" for="id">Id</label>
        <div class="controls col-md-10">
          <input type="text" class="form-control [(ngModel)]="filter.id"/>
        </div>
      </div>
      (...)
</pageLayout>

PageLayoutComponent 组件的模板可能如下：

<div *ngIf="!isFormVisible">
  <button class="btn" [ngClass]="{'btn-info': filtered, 'btn-default': !filtered}" (click)="showForm()">Filter</button>
  <button class="btn btn-default" (click)="createNew()">Create new</button>
</div>

<div class="panel panel-default" *ngIf="isFormVisible">
  <div class="panel-heading">
    <h3 class="panel-title">Filter<button type="button" class="close" (click)="hideForm()">&times;</button></h3>
  </div>
  <div class="panel-body form-horizontal">
    <ng-content></ng-content>
  </div>
</div>