Alerts provides contextual messages for typical user actions like info, error with available and flexible alert messages.

AlertComponent

Displays collapsible content panels for presenting information in a limited amount of space.

selector

• alert,bs-alert

Inputs

• dismissible − boolean, If set, displays an inline “Close” button, default: false

• dismissOnTimeout − string | number, Number in milliseconds, after which alert will be closed

• isOpen − boolean, Is alert visible, default: true

• type − string, alert type. Provides one of four bootstrap supported contextual classes: success, info, warning and danger, default: warning

Outputs

• onClose − This event fires immediately after close instance method is called, $event is an instance of Alert component.

• onClosed − This event fires when alert closed, $event is an instance of Alert component

AlertConfig

Properties

• dismissible − boolean, is alerts are dismissible by default, default: false

• dismissOnTimeout − number, default time before alert will dismiss, default: undefined

• type − string, default alert type, default: warning

Example

As we”re going to use alerts, We”ve to update app.module.ts used in ngx-bootstrap Accordion chapter to use AlertModule and AlertConfig.

Update app.module.ts to use the AlertModule and AlertConfig.

app.module.ts

import { BrowserModule } from ''@angular/platform-browser'';
import { NgModule } from ''@angular/core'';
import { BrowserAnimationsModule } from ''@angular/platform-browser/animations'';
import { AppComponent } from ''./app.component'';
import { TestComponent } from ''./test/test.component'';
import { AccordionModule } from ''ngx-bootstrap/accordion'';
import { AlertModule, AlertConfig } from ''ngx-bootstrap/alert'';
@NgModule({
   declarations: [
      AppComponent,
      TestComponent
   ],
   imports: [
      BrowserAnimationsModule,
      BrowserModule,
      AccordionModule,
      AlertModule
   ],
   providers: [AlertConfig],
   bootstrap: [AppComponent]
})
export class AppModule { }

Update test.component.html to use the alerts.

test.component.html

<alert type="success" 
   [dismissible]="dismissible"
   [isOpen]="open"
   (onClosed)="log($event)"
   [dismissOnTimeout]="timeout">
   <h4 class="alert-heading">Well done!</h4>
   <p>Success Message</p>
</alert>
<alert type="info">
   <strong>Heads up!</strong> Info
</alert>
<alert type="warning">
   <strong>Warning!</strong> Warning
</alert>
<alert type="danger">
   <strong>Oh snap!</strong> Error
</alert>

Update test.component.ts for corresponding variables and methods.

test.component.ts

import { Component, OnInit } from ''@angular/core'';
@Component({
   selector: ''app-test'',
   templateUrl: ''./test.component.html'',
   styleUrls: [''./test.component.css'']
})
export class TestComponent implements OnInit {
   open: boolean = true;
   dismissible: boolean = true;
   timeout: number = 10000;
   constructor() { }
   
   ngOnInit(): void {
   }
   log(alert){
      console.log(''alert message closed'');
   }
}

Build and Serve

Run the following command to start the angular server.

ng serve

Once server is up and running. Open http://localhost:4200 and verify the following output.