Question

I’m attempting to translate the following C# code into IronPython but I don’t know how to handle the strongly typed mutable arrays. The code is test code to write a Server Side SSRS report to a local PDF, and runs fine in C#.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using System.Data;
using System.Drawing.Imaging;
using System.Drawing.Printing;
using System.Collections.Generic;
using Microsoft.Reporting.WinForms;

namespace ConsoleBooking
{
    class Program
    {
        static void Main(string[] args)
        {
            ServerReport report = new ServerReport();
            report.ReportServerUrl = new Uri("http://192.168.1.29/ReportServer");
            report.ReportPath = "/Report Project Media Bookings/Business";

            Warning[] warnings;
            string[] streamids;
            string mimeType;
            string encoding;
            string filenameExtension;

            byte[] bytes = report.Render(
                "PDF", null, out mimeType, out encoding, out filenameExtension,
                 out streamids, out warnings);

            string filename = Path.Combine(Path.GetTempPath(), "business.pdf");
            using (FileStream fs = new FileStream(filename, FileMode.Create))
            {
                fs.Write(bytes, 0, bytes.Length);
            }
        }
    }
}

If I set the arrays up as

streamids = Array.CreateInstance(String, 1)

so my call looks like this

bytes = report.Render("PDF", None, mimeType, encoding, filenameExtension, streamids, warnings)

Then I get this rather enigmatic unhandled exception returned

expected StrongBox[str], got str

How should I code this?

The above report doesn’t take any parameters, but in C# these are added using

        List<ReportParameter> paramList = new List<ReportParameter>();
        paramList.Add(new ReportParameter("pBookingID", "6761", false));
        report.SetParameters(paramList);

Which again works fine for me in a related report – how do I add this in IronPython?

UPDATE: using bytes, mimeType, encoding, filenameExtension, streamids, warnings = report.Render(“PDF”, null) as suggested by Jeff Hardy gets over the immediate call, but it still crashes with a ‘too many values to unpack’ error. Arbitrarily extending the size of the arrays or adding extra parameters does not change this error – and it’s difficult to see what’s going wrong. Any ideas?

Answer 1

For the first problem, see the documentation on ref and out parameters. Basically, out parameters become part of a returned tuple. This would look something like (untested):

bytes, mimeType, encoding, filenameExtension, streamids, warnings = report.Render("PDF", null)

For the second, try:

from System.Collections.Generic import List

params = [ReportParameter("pBookingID", "6761", False), ...]
report.SetParam(List[ReportParameter](params))