how enable to click next part number ?

hello,
while clicking i showing image and parts number 1,2,3 and so forth. you can see that image as saving the above image. everything works fine. but if i click one part number , i have to close that pop up window to click next part number. but i need when you click next part number the preveous(which is poped up) should close and recently clicked part window should open.

here i put coding.

I, aspx.cs page:
Datatable dt = (DataTable)Session["parts"];
CircleHotSpot h = new CircleHotSpot(); h.X = Convert.ToInt32(dt.Rows[i]["xpos"]); h.Y = Convert.ToInt32(dt.Rows[i]["ypos"]); h.X = convertxypos(h.X); h.Y = convertxypos(h.Y);
h.Radius = 10;
h.NavigateUrl="javascript:funname("+dt.Rows.[i]["partnumber"].ToString()+")";

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