WebUserControl with file property

I'm doing a WebUserControl, and I want to add a property that show a file list in DesingView, like the property ImageUrl on an Image Control, but instead of images, th开发者_运维技巧is property accept xml files.

Sorry for my English.

I found the solution, is so easy : )

[UrlProperty]
    public string SourceFile
    {
        get
        {
            //Some Code
            return "";
        }
        set
        {
            //Some Code
        }
    }

It's to a generate a FileName property