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?

[BaatenHannes]

I'm a bit busy at the moment. But thanks for the invite.