Angular 4 Filter Search Custom Pipe

Question

So I am trying to build a custom pipe to do a search filter of multiple values in a ngFor loop. I have looked for a number of hours for a good working example, and most of them are based on previous builds and don't seem to work. So I was building the Pipe and using the console to give me the values. However, I cannot seem to get the input text to show up.

Here are the previous places I have looked to find working examples:

Angular 4 Pipe Filter

http://jilles.me/ng-filter-in-angular2-pipes/

https://mytechnetknowhows.wordpress.com/2017/02/18/angular-2-pipes-passing-multiple-filters-to-pipes/

https://plnkr.co/edit/vRvnNUULmBpkbLUYk4uw?p=preview

https://www.youtube.com/results?search_query=filter+search+angular+2

https://www.youtube.com/watch?v=UgMhQpkjCFg

Here is the code that I currently have:

component.html

<input type="text" class="form-control" placeholder="Search" ngModel="query" id="listSearch" #LockFilter>

      <div class="panel panel-default col-xs-12 col-sm-11" *ngFor="let lock of locked | LockFilter: query">
        <input type="checkbox" ngModel="lock.checked" (change)="openModal($event, lock)" class="check" id="{{lock.ID}}">
        <label for="{{lock.ID}}" class="check-label"></label>
        <h3 class="card-text name" ngModel="lock.name">{{lock.User}}</h3>
        <h3 class="card-text auth" ngModel="lock.auth">{{lock.AuthID}}</h3>
        <h3 class="card-text form" ngModel="lock.form">{{lock.FormName}}</h3>
        <h3 class="card-text win" ngModel="lock.win">{{lock.WinHandle}}</h3>
      </div>

pipe.ts

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

@Pipe({
  name: 'LockFilter'
})

export class LockFilterPipe implements PipeTransform {
  transform(locked: any, query: string): any {
    console.log(locked); //this shows in the console
    console.log(query); //this does not show anything in the console when typing
    if(!query) {
      return locked;
    }
    return locked.filter((lock) => {
      return lock.User.toLowerCase().match(query.toLowerCase());
    });
  }
}

I have imported the pipe into the module.

I am still a little newer to Angular 4 and am trying to figure out how to make this work. Anyways thanks for your help!

I guess I will need to be more specific. I already built out a filter search in JS that does not filter all of the options, which is what I am trying to do. Not just filter the User Name. I am filtering all 4 pieces of data. I chose a Pipe as this was what Angular suggests you do as they originally used them in AngularJS. I am just trying to essentially recreate the filter pipe we had in AngularJS that they removed for performance. All options I have found don't work, or are from previous builds of Angular.

If you need anything else from my code let me know.

Answer 1

I have to implement search functionality in my local and Here is Updated your code. please do this way.

Here is the code that I have to update.

directory Structure

app/
   _pipe/
        search/
          search.pipe.ts
          search.pipe.spec.ts
app/ 
   app.component.css
   app.component.html
   app.component.ts
   app.module.ts
   app.component.spec.ts

command run for creating pipe

ng g pipe search

component.html

<input type="text" class="form-control" placeholder="Search" [(ngModel)]="query" id="listSearch">
    <div class="panel panel-default col-xs-12 col-sm-11" *ngFor="let lock of locked | LockFilter: query">
    <input type="checkbox" (change)="openModal($event, lock)" class="check" id="{{lock.ID}}">
    <label [for]="lock.ID" class="check-label"></label>
    <h3 class="card-text name">{{lock.User}}</h3>
    <h3 class="card-text auth">{{lock.AuthID}}</h3>
    <h3 class="card-text form">{{lock.FormName}}</h3>
    <h3 class="card-text win">{{lock.WinHandle}}</h3>
</div>

component.js

Note: In this file, i have to use dummy records for implementation and testing purpose.

import { Component, OnInit } from '@angular/core';
import { FormsModule }   from '@angular/forms';

@Component({
    selector: 'app-root',
    templateUrl: './app.component.html',
    styleUrls: ['./app.component.css']
})
    export class AppComponent implements OnInit{
    public search:any = '';
    locked: any[] = [];

    constructor(){}

    ngOnInit(){
        this.locked = [
            {ID: 1, User: 'Agustin', AuthID: '68114', FormName: 'Fellman', WinHandle: 'Oak Way'},
            {ID: 2, User: 'Alden', AuthID: '98101', FormName: 'Raccoon Run', WinHandle: 'Newsome'},
            {ID: 3, User: 'Ramon', AuthID: '28586', FormName: 'Yorkshire Circle', WinHandle: 'Dennis'},
            {ID: 4, User: 'Elbert', AuthID: '91775', FormName: 'Lee', WinHandle: 'Middleville Road'},
        ]
    }
}

module.ts

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { FormsModule }   from '@angular/forms';
import { AppComponent } from './app.component';
import { SearchPipe } from './_pipe/search/search.pipe';


@NgModule({
  declarations: [
    AppComponent,
    SearchPipe
  ],
  imports: [
    BrowserModule,
    FormsModule
  ],
  providers: [],
  bootstrap: [AppComponent]
})
export class AppModule { }

pipe.ts

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

@Pipe({
    name: 'LockFilter'
})

export class SearchPipe implements PipeTransform {
    transform(value: any, args?: any): any {

        if(!value)return null;
        if(!args)return value;

        args = args.toLowerCase();

        return value.filter(function(item){
            return JSON.stringify(item).toLowerCase().includes(args);
        });
    }
}

I hope you are getting the pipe functionality and this will help you.

Answer 2

Simple filterPipe for Angular 2+

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

@Pipe({
  name: 'filter'
})
export class filterPipe implements PipeTransform {

  transform(items: any[], field:string, value: string): any[] {

    if(!items) return [];
    if(!value) return items;


    return items.filter( str => {
          return str[field].toLowerCase().includes(value.toLowerCase());
        });
   }
}

Here is the HTML

<input type="text" class="form-control" placeholder="Search" id="listSearch" #search>
    <div class="panel panel-default col-xs-12 col-sm-11" *ngFor="let lock of locked | filter:'propName': search.value>
    <input type="checkbox" (change)="openModal($event, lock)" class="check" id="{{lock.ID}}">
    <label [for]="lock.ID" class="check-label"></label>
    <h3 class="card-text name">{{lock.User}}</h3>
    <h3 class="card-text auth">{{lock.AuthID}}</h3>
    <h3 class="card-text form">{{lock.FormName}}</h3>
    <h3 class="card-text win">{{lock.WinHandle}}</h3>
</div>

in HTML PropName is dummy text. In place of PropName use your any object property key.