c# - Handling streams while Batch Printing RDLC reports from a console application -

i printing reports console application. started off using manner prescribed microsoft ( http://msdn.microsoft.com/en-us/library/ms252172(v=vs.100).aspx). in technique, 1 renders report so:

report.render("image", deviceinfo, createstream, out warnings); 

where createstream callback function:

private stream createstream(string name, string filenameextension,    encoding encoding, string mimetype, bool willseek) {     stream stream = new filestream(name + "." + filenameextension,        filemode.create);     m_streams.add(stream);     return stream; } 

the idea being render reports want files, leaving streams open , collected in array. once rendered, iterate through array, using open streams send file contents printer.

this works few reports, in case, printing around 1500 1 page reports. obviously, cannot leave streams hanging open without serious degradation performance. so, modified things. created class level stream object (renderstream) use in createstream callback, , save file name in collection.

renderstream = new filestream(filename, filemode.create, fileaccess.write, fileshare.read); renderedfilelist.add(filename); 

i renderstream.dispose() after report.render() function returns.

this way streams stay closed , disposed. , after of exports done, when go print, in printpage event this:

private void printpage(object sender, printpageeventargs ev) {     using (stream stream = new filestream(renderedfilelist[filecounter], filemode.open, fileaccess.read, fileshare.read))     {         metafile pageimage = new metafile(stream);         ev.graphics.drawimage(pageimage, ev.pagebounds);     } } 

now, problem lies. while usually have no problem opening streams rendered files, 5% of attempts access files @ print-time return exceptions, reporting file not accessible because opened process. though prior stream has been disposed.

what can around this?

i face same problem , came out way around. followed approach refering your link..

kept list files created stream:

 private list<string> _emffiles = new list<string>(); 

modified createstream method to:

private stream createstream(string name, string filenameextension,    encoding encoding, string mimetype, bool willseek) {     stream stream = new filestream(name + "." + filenameextension, filemode.create);     m_streams.add(stream);      //get files     _emffiles.add(name + "." + filenameextension);      return stream; } 

so _emffiles list have emf files created stream. then, in disposed method;

public void disposed()     {         if (m_streams != null)         {             foreach (stream stream in m_streams)                 stream.close();             m_streans = null;         }          //delete every file created stream         foreach (string file in _emffiles)         {             if (file.exists(file))                 file.delete(file);         }     } 

finally called disposed method in run method:

private void run()     {         localreport report = new localreport();         report.reportpath = "report.rdlc";         report.datasources.add(new reportdatasource("sales", loadsalesdata()));          export(report);          m_currentpageindex = 0;         print();          //after finishing printing delete emf files         disposed();     } 

this approach works me. hope helps..