Set the modal property in your application to indicate how users will interact with the web form. 

Modal or Modeless

The WebDialogWindow allows you to set whether the dialog behaves as a modal or modeless (non-modal) dialog would allowing you to better control the flow of your application.
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Customizable Header

The WebDialogWindow displays a customizable header area into which you can place caption text, several buttons including such stand-by's as the close, minimize and maximize buttons seen in desktop applications.
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Enable the dialog window property settings to give users control in resizing the window. 

Resizable

Just like a resizable dialog on the desktop, you can enable your end user to resize the WebDialogWindow at run-time.
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Window State

WebDialogWindow persists whether the user has minimized, restored or maximized its appearance.
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