Angular2 如何从 ngFor 中只获取一个值

Question

我目前正在从服务器获取深层嵌套的 json 对象并使用管道解析它们。

但即使我只想获得一个值，它也会循环每个键。我怎样才能做到这一点？

这些是代码

管道

从“@angular/core”导入{管道、管道转换}；

@Pipe({name: 'keyValues'})
export class KeysPipe implements PipeTransform {
  transform(value, args:string[]) : any {
    let keys = [];
    for (let key in value) {
      keys.push({key: key, value: value[key]});
    }
    return keys;
   }
 }

Html 模板

 <div *ngFor="let detail of teaInfo | keyValues">
     <div *ngFor="let basicinfo of detail.value | keyValues">
            <p>School: {{basicinfo.value}}</p>
     </div>
 </div>

结果

school:example1

school:example2

school:example3

school:example4

school:example5

school:example6

我也试过这个

  <div *ngFor="let detail of teaInfo | keyValues">
         <div *ngFor="let basicinfo of detail.value | keyValues">
                 <p>School: {{basicinfo.value['example2']}}</p>
          </div>
      </div>

结果

 school:

 school:example2

 school:

 school:

 school:

 school:

还在循环不给值..

但我只想得到

school:example2

没有循环任何东西..

不胜感激！

Answer 1

这可能会满足您的要求：

<div *ngFor="let basicinfo of detail.value | keyValues | splice:2:1">

Angular2 如何从 ngFor 中只获取一个值

Angular2 How to get only one value from ngFor

ngfor

angular