Get length of array in ngFor after pipes transformation

Question

I have the following template:

           


        
                      

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Answer 1

@Günter Zöchbauer {{(myArray | customPipe)?.length}} - Working as Expected

Answer 2

Well, this is not well documented in the Angular doc, you can find under source code of Angular at -

https://github.com/angular/angular/blob/master/packages/common/src/directives/ng_for_of.ts

*ngFor accepts count params.

constructor(public $implicit: T, public ngForOf: NgIterable<T>, public index: number,public count: number) {
}

So we can get the count like -

<div *ngFor="let item of items | pipe; let l = count">
<div>{{count}}</div>
</div>

Answer 3

<div *ngFor="let item of myArray | customPipe1 | customPipe2 as result">
  Here is the length of my ngFor : {{result.length}}
</div>

See also https://angular.io/api/common/NgForOf

Answer 4

Another solution could be the following

<div *ngFor="let item of myArray | customPipe1 | customPipe2; let l = count">
  Here is the length of my ngFor : {{l}}
</div>

Plunker Example

See also

• https://github.com/angular/angular/blob/master/packages/common/src/directives/ng_for_of.ts#L15-L17