The MultiView control is a container for a group of View controls. What the MultiView control is good for is creating multistep processes. Each view control can contain a series of controls that you create. Use the ActiveViewIndex property can be used to set which view is currently being displayed. Only one view at a time can be displayed, but this can be a great way to implment multistep processes where you previously used panels.
For more information:
ms-help://MS.VSCC.v80/MS.MSDNQTR.v80.en/MS.MSDN.v80/MS.VisualStudio.v80.en/cpref/html/T_System_Web_UI_WebControls_MultiView.htm
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