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PromptBox Tools

Updated on Feb 11, 2026

The PromptBox provides several built-in tools that enhance functionality and user experience.

These tools include the Action Button for submitting prompts, the File Select Button for attaching files, and the Speech-to-Text Button for voice input. In case you need additional tools, refer to the PromptBox Adornments article.

Action Button

The action button submits the prompt. Customize its appearance and behavior by setting the ActionButton option.

The button supports loading state for better user feedback during prompt submission and icon customizations for each state.

Razor

    @(Html.Kendo().PromptBox()
        .Name("promptBox")
        .ActionButton(button => button
            .Icon("sparkles")
            .FillMode(FillMode.Flat)
        )
    )

Speech-to-Text Button

The speech-to-text button enables you to input prompts with voice commands. Customize its appearance and behavior by setting the SpeechToText option. The button provides visual feedback during the speech recognition process.

Razor

    @(Html.Kendo().PromptBox()
        .Name("promptBox")
        .SpeechToText(true)
    )

File Select Button

The file select button allows you to attach files to prompts. Customize its appearance, behavior and file restrictions by setting the FileAttachment option.

To enable file attachments in the PromptBox, set the FileAttachment option to true or use a configuration object for further customization.

Razor

    @(Html.Kendo().PromptBox()
        .Name("promptBox")
        .FileAttachment(button => button
            .Multiple(true)
            .Restrictions(r => r.AllowedExtensions(new[] { ".jpg", ".png" }))
        )
    )

Attaching Multiple Files

You can allow users to attach multiple files by setting the Multiple option of the FileAttachment configuration.

Razor

    @(Html.Kendo().PromptBox()
        .Name("promptBox")
        .FileAttachment(button => button
            .Multiple(true)
        )
    )

File Size Restrictions

You can restrict the maximum file size for attachments by setting the MaxFileSize option in the Restrictions configuration of the FileAttachment setting.

Razor

    @(Html.Kendo().PromptBox()
        .Name("promptBox")
        .FileAttachment(button => button
            .Restrictions(r => r.MaxFileSize(1048576))
        )
    )

File Type Restrictions

You can restrict the allowed file types for attachments by setting the AllowedExtensions option in the Restrictions configuration of the FileAttachment setting.

Razor

    @(Html.Kendo().PromptBox()
        .Name("promptBox")
        .FileAttachment(button => button
             .Restrictions(r => r.AllowedExtensions(new[] { ".png", ".jpg", ".jpeg" }))
        )
    )