Validating existence of image URL in report
Posted on 2009-02-10
I'm trying to validate the existence of an image URL for a report page in SQL Server Reporting Services. The image URL is dynamically created based on an item number. I either display the found image at the URL or a special image that indicates there are is no image for the item. All of the images are on a virtual directory on the same server as the report server.
I've tried specifying the folder path \\servername\... and that does not work (as I would expect). I also tried specifying custom code in the report using a programmatic web request (HttpWebRequest). I expected that, but when I use it I get the following exception:
System.Security.SecurityException: Request for the permission of type 'System.Net.WebPermission, System, Version=22.214.171.124, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.
at System.Security.CodeAccessSecurityEngine.Check(Object demand, StackCrawlMark& stackMark, Boolean isPermSet)
at System.Net.HttpWebRequest..ctor(Uri uri, ServicePoint servicePoint)
at System.Net.HttpRequestCreator.Create(Uri Uri)
at System.Net.WebRequest.Create(Uri requestUri, Boolean useUriBase)
at System.Net.WebRequest.Create(String requestUriString)
at ReportExprHostImpl.CustomCodeProxy.UrlExists(String u)
The action that failed was:
The type of the first permission that failed was:
The Zone of the assembly that failed was:
This works in Visual Studio but does not work on the report server or another server on the network. I need a method that works to perform this validation or work around it so that the special image is shown if the other image is missing.