ASPxAutoCompleteBoxBase.Callback Event
Fires after the client PerformCallback method initiates a callback and during each subsequent internal callback.
Namespace: DevExpress.Web
Assembly: DevExpress.Web.v23.2.dll
NuGet Package: DevExpress.Web
Declaration
Event Data
The Callback event's data class is CallbackEventArgsBase. The following properties provide information specific to this event:
| Property | Description |
|---|---|
| Parameter | Gets a string that contains specific information (if any) passed from the client side. |
Remarks
The Callback event allows you to perform server-side actions and update editor content in response to a call to the client PerformCallback method. A common application of the Callback event is dynamic data binding. The Parameter property contains information passed from the client as the PerformCallback method parameter.
After the PerformCallback method is called on the client, the Callback event handler is raised during each page postback with the same Parameter value. This allows the control to process inner callbacks (for instance, item scrolling or filtering) with the correct item collection defined in the custom user callback.
You can change the control’s value and selection on a callback invoked by the PerformCallback method. If the event is invoked by an internal callback, the control does not apply the value and selection settings.
It is not possible to modify the control on callbacks, for instance, modify a column collection or change selection mode. To perform such actions, wrap the control in the ASPxCallbackPanel control and process the required scenario on the panel callback.
Handle BeginCallback and EndCallback client events to perform actions on the client side before and after callback processing.