We will discover how to create a custom autofocus directive in an Angular application in this tutorial.

Required conditions
Basic familiarity with Angular 2 or later; installation of Node and NPM; Visual Studio Code; Bootstrap (Optional)

Make an Angular Project
The command to create an Angular project is as follows.
ng new angapp

Now install Bootstrap by using the following command,
npm install bootstrap --save

Now open the styles.css file and add Bootstrap file reference. To add a reference in the styles.css file add this line.
@import '~bootstrap/dist/css/bootstrap.min.css';

Create  Directive
Create  a new directive using the Angular CLI command
ng generate directive autofocus

Now open autofocus.directive.ts file and add following code
import { Directive, ElementRef, AfterViewInit } from '@angular/core';

@Directive({
  selector: '[Autofocus]'
})
export class AutofocusDirective implements AfterViewInit {
  constructor(private el: ElementRef) {}

  ngAfterViewInit() {
    this.el.nativeElement.focus();
  }
}

Now open app.component.html file and add the following code.
<div class="container" style="margin-top:10px;margin-bottom: 24px;">
  <div class="col-sm-12 btn btn-info">
    Autofocus Directive in Angular Application
  </div>
</div>
<div class="container">
  <input type="text" class="form-control" placeholder="Auto Focused Textbox" Autofocus />
</div>

Now open app.module.ts and following code
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule } from '@angular/forms';
import { HttpClientModule } from '@angular/common/http';
import { AppRoutingModule } from './app-routing.module';
import { AppComponent } from './app.component';
import { AutofocusDirective } from './autofocus.directive';


@NgModule({
  declarations: [
    AppComponent, AutofocusDirective
  ],
  imports: [
    BrowserModule,
    AppRoutingModule,
    FormsModule,
    HttpClientModule
  ],
  providers: [],
  bootstrap: [AppComponent],

})
export class AppModule { }

Now run the application using npm start and check the result.

We discovered how to make a personalized autofocus directive in an Angular application by reading this post.