I have been converting one of my side projects from ASP.Net WebForms to ASP.Net MVC.  In order to reuse some of my existing ASP.net UserControls from WebForms in ASP.Net MVC, I tweaked a rending method found here and here.

I improved on these methods by enabling the caller of the utility function to be the one to set properties on the UserControl in a strongly typed fashion. The is no reflection or any other special interface needed on the user control.  The key was adding a callback.

Here is what it looks like to call and render the control to a string by the caller.  In this example I am rendering my GoogleMap UserControl to a string.  The last argument I am passing is an anonymous method that is called by the utility function to initialize my control.

UIUtil.RenderUserControl<GoogleMap>("~/UserControls/GoogleMap.ascx",
    uc =>
    {
        uc.CollegeToShow = CollegeToShow;
        uc.Height = Height;
        uc.Width = Width;
        uc.Mode = Mode;
    });

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