/// <summary>
 /// Resolve image URL for specified button type. Returns null for Button, Link and CustomImage.
 /// </summary>
 /// <param name="buttonType"></param>
 /// <param name="specifiedImageUrl"></param>
 /// <returns></returns>
 private static string ResolveImageUrl(ButtonRenderTypes buttonType, string specifiedImageUrl)
 {
     switch (buttonType)
     {
         case ButtonRenderTypes.Button:
         case ButtonRenderTypes.Link:
             return null;
         case ButtonRenderTypes.CustomImage:
             return Kit.ResolveAbsoluteUrl(specifiedImageUrl);
         default:
             return Kit.ResolveAbsoluteUrl(string.Format(CultureInfo.InvariantCulture, "~/resources/images/{0}.gif", buttonType.ToString().Replace("Image", "")));
     }
 }
 /// <summary>
 /// Get image URL for specified button type. Returns null for Button, Link and CustomImage.
 /// </summary>
 /// <param name="buttonType"></param>
 /// <returns></returns>
 protected static string GetImageUrl(ButtonRenderTypes buttonType)
 {
     switch (buttonType)
     {
         case ButtonRenderTypes.Button:
         case ButtonRenderTypes.Link:
         case ButtonRenderTypes.CustomImage:
             return null;
         default:
             return string.Format("{0}/Resources/Images/{1}.gif", Kit.WebSiteBaseUrl, buttonType.ToString().Replace("Image", ""));
     }
 }