Slow to export - Githubissues

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Do you want to request a feature or report a bug?

[x] Bug
[ ] Feature
[ ] Question

Did you test against the latest CI build?

[x] Yes
[ ] No

If you answered No, please test with the latest development build first.

Version of ClosedXML

v 0.101.0

Version of ClosedXML.Report

v 0.2.8

What is the current behavior?

I have an Excel template that I turn into a Stream so the data from a grid can export to the template using ClosedXML.Report. I have an array[18000] with about 18000 rows and 8 columns, all just strings from a datagrid. When I export it using ClosedXML, it takes like 5-10mins before it shows me the "Save To" location popup, and the file size is only like 1.3mb. Whereas when the array is 1000 rows, it only takes a couple seconds. I'm not sure if using the ClosedXML.Report for the template has to do with the performance or not, but it does get stuck after template.Generate();

What is the expected behavior or new feature?

I was using ClosedXML version 0.95.0 and I expected the performance to increase, but its roughly the same.

Is this a regression from the previous version?

See above

Reproducibility

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Code to reproduce problem:


using ClosedXML.Excel;
using ClosedXML.Report;

   var template = new XLTemplate(StreamTemplate); // this is the Excel Template I created, type Stream
   SomeArray[] data; // 18000+ rows of data from a grid
   template.AddVariable("VariableName", data) // variable is from the Excel template
   template.Generate(); // when I debug and step over here, this is where it takes a long time before the 'File save to location' pops up
   IXLWorkbook workbook = template.Workbook;
   MemoryStream ExcelStream = new();
   workbook.SaveAs(ExcelStream);

[ ] I attached a sample spreadsheet. (You can drag files on to this issue)

Thanks!

ClosedXML / ClosedXML.Report

Slow to export #341

Read and complete the full issue template

Reproducibility