Filtering an array in angular2
There is no way to do that using a default pipe. Here is the list of supported pipes by default: https://github.com/angular/angular/blob/master/modules/angular2/src/common/pipes/common_pipes.ts.
That said you can easily add a pipe for such use case:
import {Injectable, Pipe} from 'angular2/core';
@Pipe({
name: 'myfilter'
})
@Injectable()
export class MyFilterPipe implements PipeTransform {
transform(items: any[], args: any[]): any {
return items.filter(item => item.id.indexOf(args[0]) !== -1);
}
}
And use it:
import { MyFilterPipe } from './filter-pipe';
(...)
@Component({
selector: 'my-component',
pipes: [ MyFilterPipe ],
template: `
<ul>
<li *ngFor="#element of (elements | myfilter:'123')">(...)</li>
</ul>
`
})
Hope it helps you, Thierry
I have a similar scenario in one of my samples
<input "(keyup)="navigate($event)" />
<div *ngFor="#row of visibleRows"></div>
......
navigate($event){
this.model.navigate($event.keyCode);
this.visibleRows = this.getVisibleRows();
}
getVisibleRows(){
return this.model.rows.filter((row) => row.rowIndex >= this.model.start && row.rowIndex < this.model.end);
}
My approach is to recalculate the array on some qualifying event. In my case it's keyup. It may seem convenient to bind to a function or filter, but it's recommended to bind to the array directly instead. This is because the change tracking will get confused since the function/filter will return a new array instance every time change tracking is triggered - regardless of what triggered it.
Here is the full source: https://github.com/thelgevold/angular-2-samples/tree/master/components/spreadsheet
I also have a demo: http://www.syntaxsuccess.com/angular-2-samples/#/demo/spreadsheet