Angular 2 filter/search list

Solution 1:

Search by multiple fields

Assuming Data:

items = [
  {
    id: 1,
    text: 'First item'
  },
  {
    id: 2,
    text: 'Second item'
  },
  {
    id: 3,
    text: 'Third item'
  }
];

Markup:

<input [(ngModel)]="query">
<div *ngFor="let item of items | search:'id,text':query">{{item.text}}</div>

Pipe:

import {Pipe, PipeTransform} from '@angular/core';

@Pipe({
  name: 'search'
})
export class SearchPipe implements PipeTransform {
  public transform(value, keys: string, term: string) {

    if (!term) return value;
    return (value || []).filter(item => keys.split(',').some(key => item.hasOwnProperty(key) && new RegExp(term, 'gi').test(item[key])));

  }
}

One line for everything!

Solution 2:

You have to manually filter result based on change of input each time by keeping listener over input event. While doing manually filtering make sure you should maintain two copy of variable, one would be original collection copy & second would be filteredCollection copy. The advantage for going this way could save your couple of unnecessary filtering on change detection cycle. You may see a more code, but this would be more performance friendly.

Markup - HTML Template

<md-input #myInput placeholder="Item name..." [(ngModel)]="name" (input)="filterItem(myInput.value)"></md-input>

<div *ngFor="let item of filteredItems">
   {{item.name}}
</div>

Code

assignCopy(){
   this.filteredItems = Object.assign([], this.items);
}
filterItem(value){
   if(!value){
       this.assignCopy();
   } // when nothing has typed
   this.filteredItems = Object.assign([], this.items).filter(
      item => item.name.toLowerCase().indexOf(value.toLowerCase()) > -1
   )
}
this.assignCopy();//when you fetch collection from server.

Solution 3:

HTML

<input [(ngModel)] = "searchTerm" (ngModelChange) = "search()"/>
<div *ngFor = "let item of items">{{item.name}}</div>

Component

search(): void {
    let term = this.searchTerm;
    this.items = this.itemsCopy.filter(function(tag) {
        return tag.name.indexOf(term) >= 0;
    }); 
}

Note that this.itemsCopy is equal to this.items and should be set before doing the search.