SSRS -External image not rendering on HTML report - reporting-services

Question

I am working on SSRS Report. I have a report with an external image embedded in it
This renders fine inside the report viewer.
but when I render report in HTML 4.0 format in my application via web url (without using report viewer).The report that comes back from all the data except the image is not in the html
see the image tag looks like the following:-
<img onerror="this.errored=true;" class="r1" src="http://ges-server-pc/ReportServer_SQLEXPRESS?%2FGES-MVC%2FGES_FWCR&rs%3ASessionID=vdpuofii3xtph545xelnym45&rs%3AFormat=HTML4.0&rs%3AImageID=1403af250c474da8a5f851b63a8a377b">
how can I render extrenal image on Report which is in format= HTML 4.0
Can Anybody have solution for the same It will be appreciable
Thanks in advance

Answer 1

Here is one way to ensure that your application can reliably display images dynamic rendered in a report by SSRS.
When you are using the report viewer control, a lot is done behind the scenes to keep an active session and allow access to all artifacts generated by reports requested by the user. When you are using the ReportExecution api directly there are some advanced reporting features that are just not supported. Interactive sorting, sizing, drilldown and this issue just to name a few.
Always ensuring dynamic images from reports are available to your client is pretty easy. I had to cross this hurdle a way back and I'll share the way I solved it.
In a nutshell, you are going to have to intercept the render, iterate the streams, and save each resource to a temp folder and tell ssrs to look for the image in your temp folder that is behind the web app that your end user has authenticated with.
DeviceInfo
The device info structure, mostly overlooked, is going to come in handy. In this structure you will find a StreamRoot property. You can find documents on this. It basically allows you to override the location from which SSRS will stream resources as needed. This is how you tell SSRS to look for your external images in a new location.
For each report rendered I create a temp folder using a guid prior to rendering. Also, prior to rendering you need to set the StreamRoot to this temp folder.
string physicalTempFolder = MakeNewTempFolderInTempOffOfWebRoot();
string virtualTempFolder = Path.Combine(yourWebRoot,"Temp",Path.GetDirectoryName(physicalTempFolder));
Now you have a physical and virtual pointer to your repo where the images will be saved for your report. Now update the StreamRoot in SSRS. This tells SSRS that we want to override the default location for dynamic images and whatnot.
StringBuilder devInfo = new StringBuilder();
if (YourRenderFormat=="HTML")
{
devInfo.Append("<DeviceInfo>");
devInfo.Append("<StreamRoot>" + virtualTempFolder+ "</StreamRoot>");
devInfo.Append("</DeviceInfo>");
}
With the needed device info structure build we can pass it into the render method.
string extension;
string mimeType;
string reportEncoding;
string[] streamIDs = null;
ReportExecution2005.Warning[] warnings = null;
ReportExecution2005.ExecutionHeader execHeader = new ReportExecution2005.ExecutionHeader();
ReportExecution2005.ExecutionInfo rpt = _execService.LoadReport(YourReportPath, null);
if(YourParamas!=null)
_execService.SetExecutionParameters(YourParams, "en-us");
_execService.ExecutionHeaderValue = execHeader;
_execService.ExecutionHeaderValue.ExecutionID = rpt.ExecutionID;
result = _execService.Render(format, devInfo.ToString(), out extension, out mimeType, out reportEncoding, out warnings, out streamIDs);
The render method returns the streamIDs out parameter and it is key here. Next after we call render, simply iterate all the streams that are images and call ssrs's RenderStream() method to get the images and save to your physical temp folder.
if (YourRenderFormat=="HTML"))
{
string imageEncoding = "";
// For each image stream returned by the call to render,
// render the stream and save it to the application root
string FilePath = physicalTempFolder;
byte[] image;
// For each image stream returned by the call to render,
// render the stream and save it to the application root
foreach (string streamID in streamIDs)
{
image = _execService.RenderStream("HTML4.0", streamID, null, out imageEncoding, out mimeType);
//All files are unique
File.WriteAllBytes(Path.Combine(physicalTempFolder,streamID),image);
}
}
return result;