This section describes methods that control the DataSource.
cancel(operationId)
Cancels the load operation with a specific identifier.
Parameters:
operationId:
An operation identifier.
Return Value:
true if the operation was canceled; false if it was not found.
You can use the operationId field that extends the Promise object returned from the load() and reload() methods to access the operation identifier.
jQuery
index.js
var ds = new DevExpress.data.DataSource({ // DataSource is configured here});var loadPromise = ds.load();loadPromise.done(function (result) { // ...});ds.cancel(loadPromise.operationId);NOTE
Calling this method does not interrupt the HTTP request.
dispose()
Disposes of all the resources allocated to the DataSource instance.
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ // DataSource is configured here});ds.dispose();Angular
TypeScript
import { ..., OnDestroy } from '@angular/core';import DataSource from "devextreme/data/data_source";// ...export class AppComponent implements OnDestroy { ds: DataSource; constructor() { this.ds = new DataSource({ // DataSource is configured here }); } ngOnDestroy() { this.ds.dispose(); }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});export default { data() { return { ds } }, beforeDestroy() { ds.dispose(); }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});class App extends React.Component { componentWillUnmount() { ds.dispose(); } // ...}export default App;NOTE
Do not call this method if the DataSource instance was created by a UI component.
filter()
Gets the filter property's value.
Return Value:
A filter expression.
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ // ... filter: ["age", ">", 18]});var filterExpr = ds.filter(); // returns ["age", ">", 18]Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ // ... filter: ["age", ">", 18] }); let filterExpr = this.ds.filter(); // returns ["age", ">", 18] }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // ... filter: ['age', '>', 18]});export default { data() { return { ds } }, mounted() { this.filterExpr = ds.filter(); // returns ["age", ">", 18] }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // ... filter: ['age', '>', 18]});class App extends React.Component { constructor(props) { super(props); this.filterExpr = ds.filter(); // returns ["age", ">", 18] }}export default App;See Also
- Filtering
filter(filterExpr)
Sets the filter property's value.
Parameters:
filterExpr:
A filter expression.
Pass null to clear filtering settings.
Call the load() method to update the UI component bound to the DataSource:
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ // DataSource is configured here});ds.filter(["age", ">", 18]);// or// ds.filter("age", ">", 18);ds.load();Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ // DataSource is configured here }); this.ds.filter(["age", ">", 18]); // or // this.ds.filter("age", ">", 18); this.ds.load(); }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});export default { data() { return { ds } }, mounted() { ds.filter(['age', '>', 18]); // or // ds.filter('age', '>', 18); ds.load(); }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});class App extends React.Component { constructor(props) { super(props); ds.filter(['age', '>', 18]); // or // ds.filter('age', '>', 18); ds.load(); }}export default App;See Also
- Filtering
group()
Gets the group property's value.
Return Value:
A group expression.
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ // ... group: { selector: "employeeID", desc: true }});var groupExpr = ds.group(); // returns { selector: "employeeID", desc: true }Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ // ... group: { selector: "employeeID", desc: true } }); let groupExpr = this.ds.group(); // returns { selector: "employeeID", desc: true } }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // ... group: { selector: 'employeeID', desc: true }});export default { data() { return { ds } }, mounted() { this.groupExpr = ds.group(); // returns { selector: "employeeID", desc: true } }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // ... group: { selector: 'employeeID', desc: true }});class App extends React.Component { constructor(props) { super(props); this.groupExpr = ds.group(); // returns { selector: "employeeID", desc: true } }}export default App;See Also
- Grouping
group(groupExpr)
Sets the group property's value.
Parameters:
groupExpr:
A group expression.
Call the load() method to update the UI component bound to the DataSource:
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ // DataSource is configured here});ds.group({ selector: "employeeID", desc: true });ds.load();Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ // DataSource is configured here }); this.ds.group({ selector: "employeeID", desc: true }); this.ds.load(); }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});export default { data() { return { ds } }, mounted() { ds.group({ selector: 'employeeID', desc: true }); ds.load(); }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});class App extends React.Component { constructor(props) { super(props); ds.group({ selector: 'employeeID', desc: true }); ds.load(); }}export default App;See Also
- Grouping
isLastPage()
Checks whether the count of items on the current page is less than the pageSize. Takes effect only with enabled paging.
Return Value:
true if the item count is less than the pageSize; otherwise false.
isLoaded()
Checks whether data is loaded in the DataSource.
Return Value:
true if data is loaded; otherwise false.
isLoading()
Checks whether data is being loaded in the DataSource.
Return Value:
true if data is being loaded; otherwise false.
items()
Gets an array of data items on the current page.
Return Value:
Array<any>
Data items.
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ // DataSource is configured here});var dataItems = ds.items();Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ // DataSource is configured here }); let dataItems = this.ds.items(); }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});export default { data() { return { ds } }, mounted() { this.dataItems = ds.items(); }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});class App extends React.Component { constructor(props) { super(props); this.dataItems = ds.items(); }}export default App;key()
Gets the value of the underlying store's key property.
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ store: { // ... key: "ProductID" }});var keyProps = ds.key(); // returns "ProductID"Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ store: { // ... key: "ProductID" } }); let keyProps = this.ds.key(); // returns "ProductID" }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ store: { // ... key: 'ProductID' }});export default { data() { return { ds } }, mounted() { this.keyProps = ds.key(); // returns "ProductID" }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ store: { // ... key: 'ProductID' }});class App extends React.Component { constructor(props) { super(props); this.keyProps = ds.key(); // returns "ProductID" }}export default App;See Also
- key in ArrayStore | CustomStore | LocalStore | ODataStore
load()
Starts loading data.
A Promise that is resolved after data is loaded.It is a native Promise or a jQuery.Promise when you use jQuery.
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ // DataSource is configured here});ds.load() .done(function (data) { // Process "data" here }) .fail(function (error) { // Handle the "error" here });Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ // DataSource is configured here }); this.ds.load() .then( (data) => { /* Process "data" here */ }, (error) => { /* Handle the "error" here */ } ) }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});export default { data() { return { ds } }, mounted() { ds.load() .then( (data) => { /* Process "data" here */ }, (error) => { /* Handle the "error" here */ } ) }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});class App extends React.Component { constructor(props) { super(props); ds.load() .then( (data) => { /* Process "data" here */ }, (error) => { /* Handle the "error" here */ } ) }}export default App;The Promise returned from this method is extended with the operationId field which you can use to cancel the invoked operation. See cancel(operationId) for details.
See Also
- reload()
loadOptions()
Gets an object with current data processing settings.
Return Value:
Data processing settings.
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ // DataSource is configured here});var loadOptions = ds.loadOptions();Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ // DataSource is configured here }); let loadOptions = this.ds.loadOptions(); }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});export default { data() { return { ds } }, mounted() { this.loadOptions = ds.loadOptions(); }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});class App extends React.Component { constructor(props) { super(props); this.loadOptions = ds.loadOptions(); }}export default App;off(eventName)
Detaches all event handlers from a single event.
Parameters:
eventName:
The event's name.
Return Value:
DataSource
The object for which this method is called.
See Also
jQuery
- Handle Events
Angular
- Event Handling
Vue
- Event Handling
React
- Event Handling
off(eventName, eventHandler)
Detaches a particular event handler from a single event.
Return Value:
DataSource
The object for which this method is called.
See Also
jQuery
- Handle Events
Angular
- Event Handling
Vue
- Event Handling
React
- Event Handling
on(eventName, eventHandler)
Subscribes to an event.
Return Value:
DataSource
The object for which this method is called.
Use this method to subscribe to one of the events listed in the Events section.
See Also
jQuery
- Handle Events
Angular
- Event Handling
Vue
- Event Handling
React
- Event Handling
on(events)
Subscribes to events.
Parameters:
events:
Events with their handlers: { "eventName1": handler1, "eventName2": handler2, ...}
Return Value:
DataSource
The object for which this method is called.
Use this method to subscribe to several events with one method call. Available events are listed in the Events section.
See Also
jQuery
- Handle Events
Angular
- Event Handling
Vue
- Event Handling
React
- Event Handling
pageIndex(newIndex)
Sets the index of the page that should be loaded on the next load() method call.
Parameters:
newIndex:
A zero-based page index.
Call the load() method to update the UI component bound to the DataSource:
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ // ... paginate: true, pageSize: 10});ds.pageIndex(2);ds.load();Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ // ... paginate: true, pageSize: 10 }); this.ds.pageIndex(2); this.ds.load(); }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // ... paginate: true, pageSize: 10});export default { data() { return { ds } }, mounted() { ds.pageIndex(2); ds.load(); }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // ... paginate: true, pageSize: 10});class App extends React.Component { constructor(props) { super(props); ds.pageIndex(2); ds.load(); }}export default App;pageSize(value)
Sets the page size.
Parameters:
value:
A new page size value.
Call the load() method to update the UI component bound to the DataSource:
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ // ... paginate: true, pageSize: 10});ds.pageSize(15);ds.load();Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ // ... paginate: true, pageSize: 10 }); this.ds.pageSize(15); this.ds.load(); }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // ... paginate: true, pageSize: 10});export default { data() { return { ds } }, mounted() { ds.pageSize(15); ds.load(); }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // ... paginate: true, pageSize: 10});class App extends React.Component { constructor(props) { super(props); ds.pageSize(15); ds.load(); }}export default App;paginate(value)
Sets the paginate property's value.
Parameters:
value:
A new value.
Call the load() method to update the UI component bound to the DataSource:
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ // ... paginate: true, pageSize: 10});ds.paginate(false);ds.load();Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ // ... paginate: true, pageSize: 10 }); this.ds.paginate(false); this.ds.load(); }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // ... paginate: true, pageSize: 10});export default { data() { return { ds } }, mounted() { ds.paginate(false); ds.load(); }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // ... paginate: true, pageSize: 10});class App extends React.Component { constructor(props) { super(props); ds.paginate(false); ds.load(); }}export default App;reload()
Clears currently loaded DataSource items and calls the load() method.
A Promise that is resolved after loading is completed and rejected after loading failed.It is a native Promise or a jQuery.Promise when you use jQuery.
DataSource reloads data starting from the current page index. To reload all data, set pageIndex to 0 before you call reload().
The Promise returned from this method is extended with the operationId field which you can use to cancel the invoked operation. See cancel(operationId) for details.
requireTotalCount()
Gets the requireTotalCount property's value.
Return Value:
The property's value.
requireTotalCount(value)
Sets the requireTotalCount property's value.
Parameters:
value:
A new value.
Call the load() method to update the UI component bound to the DataSource:
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ // ... requireTotalCount: true});ds.requireTotalCount(false);ds.load();Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ // ... requireTotalCount: true }); this.ds.requireTotalCount(false); this.ds.load(); }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // ... requireTotalCount: true});export default { data() { return { ds } }, mounted() { ds.requireTotalCount(false); ds.load(); }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // ... requireTotalCount: true});class App extends React.Component { constructor(props) { super(props); ds.requireTotalCount(false); ds.load(); }}export default App;searchExpr()
Gets the searchExpr property's value.
The property's value; described in the Getters and Setters section.
searchExpr(expr)
Sets the searchExpr property's value.
Parameters:
A new value; described in the Getters and Setters section.
searchOperation()
Gets the searchOperation property's value.
Return Value:
The property's value.
searchOperation(op)
Sets the searchOperation property's value.
Parameters:
op:
A new value. Can be one of the following: "=", "<>", ">", ">=", "<", "<=", "startswith", "endswith", "contains" and "notcontains".
searchValue()
Gets the searchValue property's value.
Return Value: any
The property's value.
searchValue(value)
Sets the searchValue property's value.
Parameters:
value: any
A new value.
Call the load() method to update the UI component bound to the DataSource:
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ // DataSource is configured here});ds.searchExpr("firstName");ds.searchOperation("contains");ds.searchValue("Jo");ds.load();Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ // DataSource is configured here }); this.ds.searchExpr("firstName"); this.ds.searchOperation("contains"); this.ds.searchValue("Jo"); this.ds.load(); }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});export default { data() { return { ds } }, mounted() { ds.searchExpr('firstName'); ds.searchOperation('contains'); ds.searchValue('Jo'); ds.load(); }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});class App extends React.Component { constructor(props) { super(props); ds.searchExpr('firstName'); ds.searchOperation('contains'); ds.searchValue('Jo'); ds.load(); }}export default App;See Also
- Data Layer - Search API
select()
Gets the select property's value.
Return Value: any
A select expression.
See Also
- Select Expressions
select(expr)
Sets the select property's value.
Parameters:
expr: any
A select expression.
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ // DataSource is configured here});ds.select(["firstName", "lastName", "birthDate"]);// or// ds.select("firstName", "lastName", "birthDate");Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ // DataSource is configured here }); this.ds.select(["firstName", "lastName", "birthDate"]); // or // this.ds.select("firstName", "lastName", "birthDate"); }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});export default { data() { return { ds } }, mounted() { ds.select(['firstName', 'lastName', 'birthDate']); // or // ds.select('firstName', 'lastName', 'birthDate'); }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});class App extends React.Component { constructor(props) { super(props); ds.select(['firstName', 'lastName', 'birthDate']); // or // ds.select('firstName', 'lastName', 'birthDate'); }}export default App;See Also
- Select Expressions
sort()
Gets the sort property's value.
Return Value: any
A sort expression.
See Also
- Sorting
sort(sortExpr)
Sets the sort property's value.
Parameters:
sortExpr: any
A sort expression.
Call the load() method to update the UI component bound to the DataSource:
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ // DataSource is configured here});ds.sort({ selector: "Discount", desc: true });ds.load();Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ // DataSource is configured here }); this.ds.sort({ selector: "Discount", desc: true }); this.ds.load(); }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});export default { data() { return { ds } }, mounted() { ds.sort({ selector: 'Discount', desc: true }); ds.load(); }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // DataSource is configured here});class App extends React.Component { constructor(props) { super(props); ds.sort({ selector: 'Discount', desc: true }); ds.load(); }}export default App;See Also
- Sorting
store()
Gets the instance of the store underlying the DataSource.
Return Value:
A store instance.
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ store: { // Store is configured here }});var store = ds.store();Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ store: { // Store is configured here } }); let store = this.ds.store(); }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ store: { // Store is configured here }});export default { data() { return { ds } }, mounted() { this.store = ds.store(); }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ store: { // Store is configured here }});class App extends React.Component { constructor(props) { super(props); this.store = ds.store(); }}export default App;totalCount()
Gets the number of data items in the store after the last load() operation without paging. Takes effect only if requireTotalCount is true
Return Value:
The number of data items.
jQuery
JavaScript
var ds = new DevExpress.data.DataSource({ // ... requireTotalCount: true});var itemCount = ds.totalCount();Angular
TypeScript
import DataSource from "devextreme/data/data_source";// ...export class AppComponent { ds: DataSource; constructor() { this.ds = new DataSource({ // ... requireTotalCount: true }); let itemCount = this.ds.totalCount(); }}Vue
App.vue
<script>import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // ... requireTotalCount: true});export default { data() { return { ds } }, mounted() { this.itemCount = ds.totalCount(); }, // ...}</script>React
App.js
// ...import DataSource from 'devextreme/data/data_source';const ds = new DataSource({ // ... requireTotalCount: true});class App extends React.Component { constructor(props) { super(props); this.itemCount = ds.totalCount(); }}export default App;Was this topic helpful?
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