Call a ascx function

Hi! how can i call from my .aspx page to an ascx function or Page_load using parameters?
I call my ascx constrols like that:
Dim DynamicUserControl As ResD = LoadControl("../../w/ResD/ResD.ascx") DynamicUserControl.ID = "ResD" MyDiv.Controls.Add(DynamicUserControl)
And in this control in Page_load i call some functions taht draw some images but i want that in my aspx code, the client can choose what kind of image and then i will add again the same control showing the image's client choose.
 

 



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