Hello Amir!

Welcome to Visual WebGui!

First you need to understand that the HtmlBox control is rendered to the browser window inside an IFrame HTML element. That means that it has it's own 'window' object.
You need to know the DOM path to this window object so you would be able to access it.

Once you found it, you could add a server-client invocation (explained in Appendix 1), and call the "window.print();" function on the window object of the HtmlBox.

If you want to print after clicking a button, and you don't require a server action for this Button Click event, you could use client-client invocation (explained here) to attach the call to the "window.print();" function to the "onclick" of the Button on client-side through server-side code.

Appendix 1 - Server-client invocation:
On the Form object call the method: this.InvokeMethodWithId. This method take two parameters:
1. The JavaScript code to be executed.
2. JavaScript function arguments to be used if in section 1 you had a single function call.
In section 1 you should write the DOM path to the HtmlBox's window object + "window.print();".

Regards,

Ori Cohen
Manager of support, the Visual WebGui team