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Error Handling

Placeholder Message
Friday, June 28, 2026
Ashley Johnson, Portland

The WebForms SmartPasteButton component provides AI-powered form filling functionality with built-in error handling capabilities. This example demonstrates how to handle scenarios where the SmartPasteButton encounters errors during the paste operation, such as invalid data formats or API failures.

The current example shows how you can use the OnRequestEnd client-side event to catch errors and provide appropriate feedback to users. In this demo, when an error occurs, the phone field is marked as invalid to indicate that the smart paste operation was unsuccessful.

  • DefaultCS.aspx
  • DefaultCS.aspx.cs
  • script.js
  • style.css
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="DefaultCS.aspx.cs"  Inherits="SmartPasteButton_ErrorHandling_DefaultCS" %>

<!DOCTYPE html>
<html xmlns='http://www.w3.org/1999/xhtml'>
<head runat="server">
    <title>Telerik ASP.NET Example</title>
    <link href="../SmartPasteStyles.css" rel="stylesheet" />
    <link href="../Overview/style.css" rel="stylesheet" />
    <link href="style.css" rel="stylesheet" />
    <script src="script.js"></script>
</head>

<body>
    <form id="form1" runat="server">
    <telerik:RadScriptManager runat="server" ID="RadScriptManager1" />
    <telerik:RadSkinManager ID="RadSkinManager1" runat="server" ShowChooser="true" />
    <div class="demo-container no-bg flex-center" runat="server">
        <div class="smartpaste-container" id="smartPasteContainer">
            <telerik:RadCard runat="server">
                <telerik:CardBodyComponent runat="server">
                    <div class="events-chat">
                        <div class="chat-card">
                            <div class="chat-header">
                                <div class="chat-bot-message chat-bot-disabled">
                                    Placeholder Message
                                </div>
                                <span class="avatar"></span>
                            </div>
                            <div class="chat-date">
                                Friday, June 28, 2026
                            </div>
                            <div class="chat-message" id="chat-message">
                                Ashley Johnson, Portland
                            </div>
                            <br />
                            <div class="chat-input chat-input-disabled">
                                <input type="text" name="chatMessage" placeholder="Type a message" disabled="disabled" />
                            </div>
                        </div>
                        <div class="editor-actions">
                            <telerik:RadButton runat="server" ID="CopyButton1" Text="Copy Text" AutoPostBack="false" OnClientClicked="onCopyClick" />
                        </div>
                    </div>
                </telerik:CardBodyComponent>
            </telerik:RadCard>

            <telerik:RadCard runat="server">
                <telerik:CardBodyComponent runat="server">
                    <div class="form-wrapper">
                        <div class="control-container">
                            <label for="RadtextBox1">Full Name</label>
                            <telerik:RadTextBox runat="server" ID="RadtextBox1" EmptyMessage="Full Name" Width="250" SmartPasteDescription="Name" />
                        </div>
                        <div class="control-container">
                            <label for="RadtextBox1">City</label>
                            <telerik:RadTextBox runat="server" ID="TextBox2" EmptyMessage="City" Width="250" SmartPasteDescription="City" />
                        </div>
                        <div class="control-container">
                            <label for="RadtextBox1">Phone Number</label>
                            <telerik:RadMaskedTextBox runat="server" ID="RadMaskedTextBox1" Width="250" Mask="(###) ###-####" SmartPasteDescription="Phone Number" />
                        </div>
                        <div class="buttonDiv">
                            <telerik:RadButton RenderMode="Lightweight" ID="RadButton13" runat="server" AutoPostBack="false" ToolTip="Clear Inputs" OnClientClicked="onClearClick">
                                <Icon PrimaryIconCssClass="rbCancel"></Icon>
                            </telerik:RadButton>
                            <telerik:RadSmartPasteButton runat="server" ID="SmartPasteButton1" Text="Smart Paste" ServiceUrl="https://demos.telerik.com/service/v2/ai/smartpaste/smartpaste">
                                <ClientEvents OnRequestStart="onRequestStart" OnRequestEnd="onRequestEnd" />
                            </telerik:RadSmartPasteButton>
                        </div>
                    </div>
                </telerik:CardBodyComponent>
            </telerik:RadCard>
        </div>
    </div>
    </form>
</body>
</html>

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