DevExtreme Angular - Handle the Keyboard Events

The TextBox raises four keyboard events: keyDown, keyPress, keyUp and enterKey. Within the functions that handle them, you can access the original keyboard events. If you are not going to change the functions during the lifetime of the widget, assign them to the respective widget options.

HTML
TypeScript
  • <dx-text-box
  • (onKeyDown)="onKeyDown($event)"
  • (onKeyPress)="onKeyPress($event)"
  • (onKeyUp)="onKeyUp($event)"
  • (onEnterKey)="onEnterKey($event)">
  • </dx-text-box>
  • import { DxTextBoxModule } from "devextreme-angular";
  • // ...
  • export class AppComponent {
  • onKeyDown (e) {
  • let keyCode = e.event.key;
  • // Event handling commands go here
  • }
  • onKeyPress (e) {
  • let keyCode = e.event.key;
  • // Event handling commands go here
  • }
  • onKeyUp (e) {
  • let keyCode = e.event.key;
  • // Event handling commands go here
  • }
  • onEnterKey (e) {
  • // Event handling commands go here
  • }
  • }
  • @NgModule({
  • imports: [
  • // ...
  • DxTextBoxModule
  • ],
  • // ...
  • })

If you are going to change the handling functions at runtime, or if you need to attach several functions to a single event, use the on(eventName, eventHandler) method. This approach is more typical of jQuery.

JavaScript
  • var keyDownHandler1 = function (e) {
  • var keyCode = e.event.key;
  • // First handler of the "keyDown" event
  • };
  •  
  • var keyDownHandler2 = function (e) {
  • var keyCode = e.event.key;
  • // Second handler of the "keyDown" event
  • };
  •  
  • $("#textBoxContainer").dxTextBox("instance")
  • .on("keyDown", keyDownHandler1)
  • .on("keyDown", keyDownHandler2);

You can also implement handlers for other keys using the registerKeyHandler(key, handler) method.

TypeScript
  • import { ..., ViewChild, AfterViewInit } from "@angular/core";
  • import { DxTextBoxModule, DxTextBoxComponent } from "devextreme-angular";
  • // ...
  • export class AppComponent implements AfterViewInit {
  • @ViewChild(DxTextBoxComponent) textBox: DxTextBoxComponent
  • ngAfterViewInit () {
  • this.textBox.instance.registerKeyHandler("backspace", function (e) {
  • // The argument "e" contains information on the event
  • });
  • this.textBox.instance.registerKeyHandler("space", function (e) {
  • // ...
  • });
  • }
  • }
  • @NgModule({
  • imports: [
  • // ...
  • DxTextBoxModule
  • ],
  • // ...
  • })
See Also