Print Button Not Working if i not inital the Crystal Report Viewer

Question

hiii every body here
i have problem on my web application with framework (4.0)
i use crystal report viewer (crystal report 13) and i installed the engine of crystal report and use dataset as datasource to my report and my report work fine but ....
my problem is :
i cannot export or print my crystal report 13 if i put my code on sub like that :
protected void btn_print_Click ( object sender , EventArgs e )
            SP_testTableAdapter adpter = new SP_testTableAdapter();
            adpter.Fill(ds.SP_test);
            Reports.Learning.CrystalReports.CR_testreport my_report = new Reports.Learning.CrystalReports.CR_testreport();
            my_report.SetDataSource(ds);
            CrystalReportViewer1.ReportSource = my_report;
            CrystalReportViewer1.DataBind();
when i use this i cannot print or export it say to me login to database fail message although i use dataset not direct database connection that mean it not need to give the report source every use of it the connection of my server details like username , password
but if i put this code to my page load the report run and showing and print correctly , i need to can use print,export and every button on reportviewer toolbar
without put the code that display report on page_load i need to put code on button event only and when i click the button it show the report and can print and export , and not need to use sesssion
need help plz ................

Answer 1

An assumption here is that this is a web app. That being the case, you need to worry about post backs when you print or export. E.g.; almost any action the viewer will cause a post back and thus what ever data you sent to the report is now forgotten. Place the report in session and this will eliminate the issue. Search for KBA 1985571. I document the full code needed there.
- Ludek