Async implementation of freezing top row

[BaatenHannes]

See issue #678. Added async implementation of PR #620 Freeze top row.

[meld-cp]

Hi @BaatenHannes, thanks for the PR. :)

I think to prevent repeating the Freeze pane code for the Async versions we can do the following:

• add the following methods to \src\MiniExcel\OpenXml\ExcelOpenXmlSheetWriter.DefaultOpenXml.cs:

      private string GetSheetViews()
      {
          // exit early if no style to write
          if (_configuration.FreezeRowCount <= 0 && _configuration.FreezeColumnCount <= 0)
          {
              return string.Empty;
          }
  
          var sb = new StringBuilder();
  
          // start sheetViews
          sb.Append(WorksheetXml.StartSheetViews);
          sb.Append(WorksheetXml.StartSheetView());
  
          // Write panes
          sb.Append(GetPanes());
  
          // end sheetViews
          sb.Append(WorksheetXml.EndSheetView);
          sb.Append(WorksheetXml.EndSheetViews);
  
          return sb.ToString();
      }
  
      private string GetPanes()
      {
  
          var sb = new StringBuilder();
  
          string activePane;
          if (_configuration.FreezeColumnCount > 0 && _configuration.FreezeRowCount > 0)
          {
              activePane = "bottomRight";
          }
          else if (_configuration.FreezeColumnCount > 0)
          {
              activePane = "topRight";
          }
          else
          {
              activePane = "bottomLeft";
          }
          sb.Append(
              WorksheetXml.StartPane(
                  xSplit: _configuration.FreezeColumnCount > 0 ? _configuration.FreezeColumnCount : (int?)null,
                  ySplit: _configuration.FreezeRowCount > 0 ? _configuration.FreezeRowCount : (int?)null,
                  topLeftCell: ExcelOpenXmlUtils.ConvertXyToCell(
                      _configuration.FreezeColumnCount + 1,
                      _configuration.FreezeRowCount + 1
                  ),
                  activePane: activePane,
                  state: "frozen"
              )
          );
  
          // write pane selections
          if (_configuration.FreezeColumnCount > 0 && _configuration.FreezeRowCount > 0)
          {
              // freeze row and column
              /*
               <selection pane="topRight" activeCell="B1" sqref="B1"/>
               <selection pane="bottomLeft" activeCell="A3" sqref="A3"/>
               <selection pane="bottomRight" activeCell="B3" sqref="B3"/>
               */
              var cellTR = ExcelOpenXmlUtils.ConvertXyToCell(_configuration.FreezeColumnCount + 1, 1);
              sb.Append(WorksheetXml.PaneSelection("topRight", cellTR, cellTR));
  
              var cellBL = ExcelOpenXmlUtils.ConvertXyToCell(1, _configuration.FreezeRowCount + 1);
              sb.Append(WorksheetXml.PaneSelection("bottomLeft", cellBL, cellBL));
  
              var cellBR = ExcelOpenXmlUtils.ConvertXyToCell(_configuration.FreezeColumnCount + 1, _configuration.FreezeRowCount + 1);
              sb.Append(WorksheetXml.PaneSelection("bottomRight", cellBR, cellBR));
          }
          else if (_configuration.FreezeColumnCount > 0)
          {
              // freeze column
              /*
                 <selection pane="topRight" activeCell="A1" sqref="A1"/>
              */
              var cellTR = ExcelOpenXmlUtils.ConvertXyToCell(_configuration.FreezeColumnCount, 1);
              sb.Append(WorksheetXml.PaneSelection("topRight", cellTR, cellTR));
  
          }
          else
          {
              // freeze row
              /*
                  <selection pane="bottomLeft"/>
              */
              sb.Append(WorksheetXml.PaneSelection("bottomLeft", null, null));
  
          }
  
          return sb.ToString();
  
      }

• remove the WriteSheetViews and WritePanes methods from \src\MiniExcel\OpenXml\ExcelOpenXmlSheetWriter.cs

• replace the 3 WriteSheetViews(writer); calls in \src\MiniExcel\OpenXml\ExcelOpenXmlSheetWriter.cs with writer.Write(GetSheetViews());

• replace the await WritePanesAsync(writer); calls in this PR with await writer.WriteAsync(GetSheetViews());

• remove the WriteSheetViewsAsync(MiniExcelAsyncStreamWriter writer) and WritePanesAsync(MiniExcelAsyncStreamWriter writer) methods in this PR

This will ensure that the sync and async writers are using the same code to build the panes.

[BaatenHannes]

Hi @meld-cp, good point, didn't notice the DefaultOpenXml class. I refactored it to prevent the code duplication.

[shps951023]

@BaatenHannes 👍👍👍 Merged, could we invite you to our team?