御用小本本

• 參照：How to export Excel files from the ABP framework | ABP Community
• Nuget：只要安裝 documentformat.openxml
  dotnet add package documentformat.openxml
• Return：原本是輸出 Byte[]，這邊改用 RemoteStreamContent，好處是可以直接下載

public Task<RemoteStreamContent> ExportToExcel()
{
    var fs = new ExcelFileGenerator().Generate();
    fs.Position = 0;
    return Task.FromResult(
        new RemoteStreamContent(fs,$"test_{DateTime.Now:yyyyMMdd_HHmmss}.xlsx","application/octet-stream"));
}

• 注意：fs.Position = 0;
• RemoteStreamContent 是吃 Stream，所以 ExcelFileGenerator 要從 Byte[] 改回傳 MemoryStream

public MemoryStream Generate()
{
    var memoryStream = new MemoryStream();

    using (var document = SpreadsheetDocument.Create(memoryStream, SpreadsheetDocumentType.Workbook))
    {
        var workbookPart = document.AddWorkbookPart();
        workbookPart.Workbook = new Workbook();

        var worksheetPart = workbookPart.AddNewPart<WorksheetPart>();
        worksheetPart.Worksheet = new Worksheet(new SheetData());

        var sheets = workbookPart.Workbook.AppendChild(new Sheets());

        sheets.AppendChild(new Sheet
        {
            Id = workbookPart.GetIdOfPart(worksheetPart),
            SheetId = 1,
            Name = "Sheet 1"
        });

        var sheetData = worksheetPart.Worksheet.GetFirstChild<SheetData>();

        var row1 = new Row();
        row1.AppendChild(
            new Cell
            {
                CellValue = new CellValue("Abp Framework"),
                DataType = CellValues.String
            }

        );
        sheetData.AppendChild(row1);

        var row2 = new Row();
        row2.AppendChild(
            new Cell
            {
                CellValue = new CellValue("Open Source"),
                DataType = CellValues.String
            }
        );
        sheetData.AppendChild(row2);

        var row3 = new Row();
        row3.AppendChild(
            new Cell
            {
                CellValue = new CellValue("WEB APPLICATION FRAMEWORK"),
                DataType = CellValues.String
            }
        );
        sheetData.AppendChild(row3);

        document.Save();
        document.Close();

        return memoryStream;
    }
}

主要就把 return memoryStream.ToArray();  的 ToArray() 拿掉

延伸閱讀

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