DevExtreme DataSource
DevExtreme Data Layer components can perform two types of data operations: shaping (sorting, filtering, grouping) and modification (creation, update, deletion).
Data Shaping
Data shaping is implemented by the DataSource component and its methods. To call them, use the getDataSource() method to get a DataSource instance from your UI component. Alternatively, you can use a standalone instance saved in a constant/component property when you created the DataSource.
The following code obtains a DataSource instance using both approaches and calls one of the data shaping methods—filter(filterExpr). Such methods only set up data shaping settings. To apply them, the load() method is called.
Using a standalone DataSource instance
app.component.ts- import { Component } from '@angular/core';
- import DataSource from 'devextreme/data/data_source';
- @Component({
- selector: 'app-root',
- templateUrl: './app.component.html',
- styleUrls: ['./app.component.css']
- })
- export class AppComponent {
- dataSource: DataSource;
- constructor() {
- this.dataSource = new DataSource({
- // ...
- // DataSource is configured here
- // ...
- });
- }
- filter() {
- this.dataSource.filter(['age', '>', 18]);
- this.dataSource.load();
- }
- }
Getting a DataSource instance from the UI component (DataGrid here)
app.component.ts- import { Component } from '@angular/core';
- import { DxDataGridComponent } from 'devextreme-angular';
- @Component({
- selector: 'app-root',
- templateUrl: './app.component.html',
- styleUrls: ['./app.component.css']
- })
- export class AppComponent {
- @ViewChild(DxDataGridComponent, { static: false }) dataGrid: DxDataGridComponent;
- // Prior to Angular 8
- // @ViewChild(DxDataGridComponent) dataGrid: DxDataGridComponent;
- filter() {
- const dataSource = this.dataGrid.instance.getDataSource();
- dataSource.filter(['age', '>', 18]);
- dataSource.load();
- }
- }
Data Modification
Data modification is implemented by the store and its methods. To call them, you need a store instance that you can get using the DataSource's store() method.
Stores provide three data modification methods: insert(values), update(key, values), and remove(key). Use them to edit local and remote data. Call the DataSource's reload() method afterwards to update data in the DataSource.
- import { Component } from '@angular/core';
- import DataSource from 'devextreme/data/data_source';
- @Component({
- selector: 'app-root',
- templateUrl: './app.component.html',
- styleUrls: ['./app.component.css']
- })
- export class AppComponent {
- dataSource: DataSource;
- constructor() {
- this.dataSource = new DataSource({
- // ...
- });
- const store = this.dataSource.store();
- store.insert({ id: 1, name: "John Doe" })
- .then(
- (dataObj) => {
- this.dataSource.reload();
- },
- (error) => { /* ... */ }
- );
- store.update(1, { name: "John Smith" })
- .then(
- (dataObj) => {
- this.dataSource.reload();
- },
- (error) => { /* ... */ }
- );
- store.remove(1)
- .then(
- (key) => {
- this.dataSource.reload();
- },
- (error) => { /* ... */ }
- );
- }
- }
See Also
Local Array
Ensure that one- or two-way binding is used to bind the dataSource property to the array. Then, use standard methods to change the array. This updates the UI component automatically.
- <dx-chart ...
- [dataSource]="fruits">
- </dx-chart>
- import { Component } from '@angular/core';
- @Component({
- selector: 'app-root',
- templateUrl: './app.component.html',
- styleUrls: ['./app.component.css']
- })
- export class AppComponent {
- fruits = [
- { fruit: 'Apples', count: 10 },
- { fruit: 'Oranges', count: 12 },
- { fruit: 'Lemons', count: 15 }
- ];
- addPineapple() {
- this.fruits.push({ fruit: 'Pineapples', count: 3 });
- }
- }
- import { BrowserModule } from '@angular/platform-browser';
- import { NgModule } from '@angular/core';
- import { AppComponent } from './app.component';
- import { DxChartModule } from 'devextreme-angular';
- @NgModule({
- declarations: [
- AppComponent
- ],
- imports: [
- BrowserModule,
- DxChartModule
- ],
- providers: [ ],
- bootstrap: [AppComponent]
- })
- export class AppModule { }
See Also
If you have technical questions, please create a support ticket in the DevExpress Support Center.