Hidden Field Data - Binding HTML

You can not do like this in .aspx page
The alternative is you can write the following code in ur .aspx.cs page.

In Page Load Event write the code to get the value from hiddenfield and assign it to the imageurl property if the image or in the javascript also

sample code to do in pageload event

protected void Page_Load(object sender, EventArgs e)
{
      Image.ImageUrl = hdID.Value;
}

Try this

<asp:image id="Image" runat="server" imageurl="~/ShowImage.ashx?id='<%=hdID.Value%>'&name='<%#hdName.Value%>'" width="300" imagealign="Left"></asp:image>

I did all of the data binding in code rather than trying to make the HTML do the evals