# RadPrompt Dialog

The **RadPrompt** dialog presents a message, an area for the user to type input, and displays "OK" and "Cancel" buttons. As with the other RadWindow dialogs, the message is not limited to text: you can supply a string of HTML for richer formatting.

> important In order to use this dialog you need to have a **RadWindowManager** on the page.

At a minimum, the **RadPrompt** function takes two arguments, and HTML string with the message, and the name of a callback function that deals with the results. The argument can be read in the callback function. If the user has pressed Cancel or has closed the dialog by clicking the \[X] button, the returned argument will be *null*.

Optionally, you can add additional arguments to supply the dialog with a width, height, title, default text.

## Calling RadPrompt via JavaScript

The minimum required to show a **RadPrompt** is the content string and a callback function:

```ASP.NET
<script type="text/javascript">
	function promptCallBackFn(arg)
	{
		alert("Prompt returned the following result: " + arg);
	}
</script>
<button onclick="radprompt('What is the answer to Life, the Universe and Everything?', promptCallBackFn); return false;">
	show PROMPT BOX</button>
```

The full syntax of the radprompt() function is:

```JavaScript
var oPrompt = radprompt(text, callBackFn, oWidth, oHeight, callerObj, oTitle, defaultValue);
```

where you can set optional width, height, title default value for the **RadPrompt** dialog.

This method also returns a reference to the RadAlert object (which is essentially a RadWindow), so you can use the [RadWindow's client-side API](https://www.telerik.com/products/aspnet-ajax/documentation/controls/window/client-side-programming/radwindow-object) on it to further change it (titlebar icon, behaviors, etc.)

## Calling RadPrompt from the code-behind

Since Q1 2011 the **RadWindowManager** offers a built-in server-side method to call the **RadPrompt**:

```C#
RadWindowManager1.RadPrompt("What is the answer to Life, the Universe and Everything?", "promptCallBackFn", 350, 100, null, "Deep Thought", "42");
```

```VB
RadWindowManager1.RadPrompt("What is the answer to Life, the Universe and Everything?", "promptCallBackFn", 350, 100, Nothing, "Deep Thought", "42")
```

> note Strings passed into this method must be properly formatted and escaped for HTML and JavaScript. Please see the related article [Calling the Predefined Dialogs from the Server Methods](https://www.telerik.com/products/aspnet-ajax/documentation/controls/window/troubleshooting/calling-the-predefined-dialogs-from-the-server-methods).

> important The **callback function** is a client-side JavaScript function which is executed when the dialog is closed.

> note The **Caller object** parameter should have a null (Nothing) value, as it exists only for backwards compatibility.

The appearance of the prompt dialog is controlled by two things: the **Skin** property of the **RadWindowManager**, and the values you pass in as arguments to **RadPrompt**. The arguments can include the HTML string you pass in as a message, the width, the height, the title and the default value. The **Skin** property controls not only the appearance of the popup's title bar, but also the layout of the dialog: its icon, button style, and so on. This dialog layout and appearance is controlled by the prompt dialog template associated with the Skin. For details on how to customize the template, see [Templates](https://www.telerik.com/products/aspnet-ajax/documentation/controls/window/alert--confirm--prompt-dialogs/how-to-change-the-dialog-templates).

## See Also

* [Calling the Predefined Dialogs from the Server Methods](https://www.telerik.com/products/aspnet-ajax/documentation/controls/window/troubleshooting/calling-the-predefined-dialogs-from-the-server-methods)