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Form Fields

Updated on Feb 11, 2026

The SmartPasteButton uses form field metadata to instruct the AI service on how to extract and map clipboard content to form controls. This article explains how form fields work and how to configure them.

Automatic Field Detection

The SmartPasteButton automatically detects form fields from Telerik controls that have the SmartPasteDescription property set:

ASP.NET

<telerik:RadTextBox runat="server" ID="txtFullName" EmptyMessage="Full Name" SmartPasteDescription="Full Name" />
<telerik:RadTextBox runat="server" ID="txtCity" EmptyMessage="City" SmartPasteDescription="City" />
<telerik:RadMaskedTextBox runat="server" ID="txtPhone" Mask="(###) ###-####" SmartPasteDescription="Phone Number" />

<telerik:RadSmartPasteButton runat="server" ID="SmartPasteButton1" Text="Smart Paste" ServiceUrl="https://demos.telerik.com/service/v2/ai/smartpaste/smartpaste" />

When the SmartPasteButton is clicked, it automatically collects information from all controls with SmartPasteDescription and sends it to the AI service.

FormField Structure

The SmartPasteButton extracts form metadata in the following format:

Field — Points to the identifier of the control (e.g., txtFullName)
Description — Critical for AI accuracy - The text from the SmartPasteDescription property that provides context to the AI service
AllowedValues — Constrained values that the AI Service must choose from (for dropdowns, radio groups)

Example request sent to AI service:

json

{
  "clipboardContent": "John Smith, john@example.com, USA",
  "formFields": [
    {
      "id": "txtEmail",
      "description": "Email Address",
      "type": "string"
    },
    {
      "id": "ddlCountry",
      "description": "Select Country",
      "type": "fixed-choice",
      "allowedValues": ["USA", "Canada", "Mexico"]
    }
  ]
}

Field Types

The SmartPasteButton automatically determines the field type based on the Telerik control:

string — For RadTextBox. Expects plain text values
number — For RadNumericTextBox and RadMaskedTextBox. Expects numeric values
boolean — For RadCheckBox and RadRadioButton. Expects true or false values
fixed-choice — For RadDropDownList and RadRadioButtonList. Expects values from control's items
multiple-choice — For RadComboBox (with CheckBoxes) and RadCheckBoxList. Expects comma-separated values
date — For RadDatePicker. Expects date values
datetime — For RadDateInput. Expects date and time values

Contextual Descriptions

Use detailed descriptions in the SmartPasteDescription property to provide validation context and improve AI accuracy:

ASP.NET

<telerik:RadNumericTextBox runat="server" ID="numAge" MinValue="18" MaxValue="100" SmartPasteDescription="Age in years. Value must be between 18 and 100." />

<telerik:RadDatePicker runat="server" ID="dpDelivery" SmartPasteDescription="Preferred delivery date. Must be a future weekday." />

<telerik:RadTextBox runat="server" ID="txtEmail" SmartPasteDescription="Email address in format user@domain.com" />

The more descriptive you are, the better the AI can extract and validate the data.

Explicit Field Configuration

While automatic detection works for most scenarios, you can provide explicit field configurations using the FormFields collection for precise control:

ASP.NET

<telerik:RadTextBox runat="server" ID="txtFullName" EmptyMessage="Full Name" />
<telerik:RadTextBox runat="server" ID="txtCity" EmptyMessage="City" />
<telerik:RadMaskedTextBox runat="server" ID="txtPhone" Mask="(###) ###-####" />

<telerik:RadSmartPasteButton runat="server" ID="SmartPasteButton1" Text="Smart Paste" ServiceUrl="https://demos.telerik.com/service/v2/ai/smartpaste/smartpaste">
    <FormFields>
        <telerik:SmartPasteButtonFormField ControlID="txtFullName" Description="Full name of the person. Extract first and last name together." />
        <telerik:SmartPasteButtonFormField ControlID="txtCity" Description="City name only, without state or country." />
        <telerik:SmartPasteButtonFormField ControlID="txtPhone" Description="Phone number in format (###) ###-####. Must be exactly 10 digits." />
    </FormFields>
</telerik:RadSmartPasteButton>

Use explicit configuration when you need to:

Provide detailed descriptions for better AI understanding
Include only specific form fields while excluding others
Define allowed values for select fields
Work with controls that don't have SmartPasteDescription set

Supported Telerik AJAX Controls

The SmartPasteButton supports seamless integration with the following Telerik UI for ASP.NET AJAX controls:

Control	Type	Documentation
RadTextBox	`string`	RadTextBox Overview
RadNumericTextBox	`number`	RadNumericTextBox Overview
RadMaskedTextBox	`number`	RadMaskedTextBox Overview
RadDatePicker	`date`	RadDatePicker Overview
RadDateInput	`datetime`	RadDateInput Overview
RadCheckBox	`boolean`	RadCheckBox Overview
RadDropDownList	`fixed-choice`	RadDropDownList Overview
RadRadioButtonList	`fixed-choice`	RadRadioButtonList Overview
RadComboBox	`multiple-choice`	RadComboBox Overview
RadCheckBoxList	`multiple-choice`	RadCheckBoxList Overview