Events

Updated on Feb 11, 2026

Client-side Events of the Telerik WebForms SmartPasteButton component.

• Load
• RequestStart
• RequestEnd
• Error

Load

Fires when the SmartPasteButton component and its Kendo widget is fully initialized.

Event data

• sender - Telerik.Web.UI.RadSmartPasteButton - The SmartPasteButton instance that triggered the event.

Example

JavaScript

function onLoad(sender, args) {
    let smartPasteButton = sender; // Telerik.Web.UI.RadSmartPasteButton
    let kendoSmartPasteButton = smartPasteButton.get_kendoWidget(); // kendo.ui.SmartPasteButton
}

Attaching the event

In the Markup

ASP.NET

<telerik:RadSmartPasteButton runat="server" ID="SmartPasteButton1" ServiceUrl="https://demos.telerik.com/service/v2/ai/smartpaste/smartpaste">
    <ClientEvents OnLoad="onLoad" />
</telerik:RadSmartPasteButton>

On Client-side

JavaScript

function pageLoadHandler() {
    let smartPasteButton = $find("<%=  SmartPasteButton1.ClientID %>");

    smartPasteButton.add_load(onLoad);
}

Sys.Application.add_load(pageLoadHandler);

On Server-side

C#

protected void Page_PreInit(object sender, EventArgs e)
{
    SmartPasteButton1.ClientEvents.OnLoad = "onLoad";
}

VB

Protected Sub Page_PreInit(ByVal sender As Object, ByVal e As EventArgs) Handles Me.PreInit
    SmartPasteButton1.ClientEvents.OnLoad = "onLoad"
End Sub

RequestStart

Fires when the SmartPasteButton is about to send a request to the LLM service. This event is cancellable.

Event data

• sender - Telerik.Web.UI.RadSmartPasteButton - The SmartPasteButton instance that triggered the event.
• args - Provides accessors to request info.

Property	Return Type	Description
get_content()	string	Gets the clipboard content being sent to the service.
get_formFields()	Object	Gets the form fields configuration.
set_cancel(value)	bool	Set to true to cancel the request.

Example

JavaScript

function onRequestStart(sender, args) {
    let content = args.get_content();
    let formFields = args.get_formFields();

    if (!content) {
        args.set_cancel(true); // Cancel the request if no content
    }
}

Attaching the event

In the Markup

ASP.NET

<telerik:RadSmartPasteButton runat="server" ID="SmartPasteButton1" ServiceUrl="https://demos.telerik.com/service/v2/ai/smartpaste/smartpaste">
    <ClientEvents OnRequestStart="onRequestStart" />
</telerik:RadSmartPasteButton>

On Server-side

C#

protected void Page_PreInit(object sender, EventArgs e)
{
    SmartPasteButton1.ClientEvents.OnRequestStart = "onRequestStart";
}

VB

Protected Sub Page_PreInit(ByVal sender As Object, ByVal e As EventArgs) Handles Me.PreInit
    SmartPasteButton1.ClientEvents.OnRequestStart = "onRequestStart"
End Sub

RequestEnd

Fires when the SmartPasteButton receives a successful response from the LLM service.

Event data

• sender - Telerik.Web.UI.RadSmartPasteButton - The SmartPasteButton instance that triggered the event.
• args - Provides accessors to response info.

Property	Return Type	Description
get_fieldValues()	Object	Gets the field values returned from the LLM service.

Example

JavaScript

function onRequestEnd(sender, args) {
    let fieldValues = args.get_fieldValues();
    
    console.log("Smart paste completed:", fieldValues);
}

Attaching the event

In the Markup

ASP.NET

<telerik:RadSmartPasteButton runat="server" ID="SmartPasteButton1" ServiceUrl="https://demos.telerik.com/service/v2/ai/smartpaste/smartpaste">
    <ClientEvents OnRequestEnd="onRequestEnd" />
</telerik:RadSmartPasteButton>

On Server-side

C#

protected void Page_PreInit(object sender, EventArgs e)
{
    SmartPasteButton1.ClientEvents.OnRequestEnd = "onRequestEnd";
}

VB

Protected Sub Page_PreInit(ByVal sender As Object, ByVal e As EventArgs) Handles Me.PreInit
    SmartPasteButton1.ClientEvents.OnRequestEnd = "onRequestEnd"
End Sub

Error

Fires when an error occurs during the smart paste operation.

Event data

• sender - Telerik.Web.UI.RadSmartPasteButton - The SmartPasteButton instance that triggered the event.
• args - Error info.

Property	Return Type	Description
get_error()	string / Object	The error message or object returned.

Event handler example

JavaScript

function onError(sender, args) {
    console.error("Smart paste error:", args.get_error());
}

Attaching the event

In the Markup

ASP.NET

<telerik:RadSmartPasteButton runat="server" ID="SmartPasteButton1" ServiceUrl="https://demos.telerik.com/service/v2/ai/smartpaste/smartpaste">
    <ClientEvents OnError="onError" />
</telerik:RadSmartPasteButton>

On Server-side

C#

protected void Page_PreInit(object sender, EventArgs e)
{
    SmartPasteButton1.ClientEvents.OnError = "onError";
}

VB

Protected Sub Page_PreInit(ByVal sender As Object, ByVal e As EventArgs) Handles Me.PreInit
    SmartPasteButton1.ClientEvents.OnError = "onError"
End Sub

Next Steps

• Enums