从ASP.NET页面下载EXCEL文件而不在服务器上生成物理文件（On The Fly）

I am trying to export C# DataTable to EXCEL file on the fly (without creating physical file) using Microsoft Office EXCEL INTEROP and download it through asp.net webpage through Response object. I am able to generate memorystream using the library But somehow the file is not getting saved through the memory stream. Reference code is given below. You will be required to take reference for DocumentFormat.OpenXml.dll & WindowsBase.DLL (that you can download from microsoft site).

我正在尝试使用Microsoft Office EXCEL INTEROP将C#DataTable动态导出到EXCEL文件(不创建物理文件),并通过asp.net网页通过Response对象下载。我能够使用库生成内存流但不知何故该文件没有通过内存流保存。参考代码如下。您将需要参考DocumentFormat.OpenXml.dll和WindowsBase.DLL(您可以从microsoft站点下载)。

Any Idea how to resolve the problem ? ? ?

任何想法如何解决问题? ? ?

Private void DownloadFile()
{
                DataSet objTable = ReadTableFromViewstate();
            if (objTable != null && objTable.Rows.Count > 0)
            {

                string strDownloadableFilename = "TestExcelFileName.xls";
                MemoryStream fs1 = new MemoryStream();
                if (CreateExcelFile.CreateExcelDocument(objTable, fs1))
                {
                    Response.Clear();
                        byte[] data1 = new byte[fs1.Length];
                        fs1.Read(data1, 0, data1.Length);
                        fs1.Close();

                    Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
                    Response.AddHeader("Content-Disposition", string.Format("attachment; filename={0}", strDownloadableFilename));
                    Response.BinaryWrite(data1); ;
                   Response.End();

                }
                else
                {
                    LblErrorMessage.Text = "Error Exporting File.";
                }
            }

        }

..

public static bool CreateExcelDocument(DataSet ds, System.IO.Stream excelFileStream)
    {
        try
        {
            using (SpreadsheetDocument document = SpreadsheetDocument.Create(excelFileStream, SpreadsheetDocumentType.Workbook))
            {
                CreateParts(ds, document);
            }

            Trace.WriteLine("Successfully created: " + excelFileStream);
            return true;
        }
        catch (Exception ex)
        {
            Trace.WriteLine("Failed, exception thrown: " + ex.Message);
            return false;
        }
    }
..




private static void CreateParts(DataSet ds, SpreadsheetDocument document)
        {
            WorkbookPart workbookPart = document.AddWorkbookPart();
            Workbook workbook = new Workbook();
            workbookPart.Workbook = workbook;

            //  If we don't add a "WorkbookStylesPart", OLEDB will refuse to connect to this .xlsx file !

                WorkbookStylesPart workbookStylesPart = workbookPart.AddNewPart<WorkbookStylesPart>("rIdStyles");
            Stylesheet stylesheet = new Stylesheet();

            workbookStylesPart.Stylesheet = stylesheet;

            Sheets sheets = new Sheets();

            //  Loop through each of the DataTables in our DataSet, and create a new Excel Worksheet for each.
        uint worksheetNumber = 1;
        foreach (DataTable dt in ds.Tables)
        {
            //  For each worksheet you want to create
            string workSheetID = "rId" + worksheetNumber.ToString();
            string worksheetName = dt.TableName;

            WorksheetPart worksheetPart = workbookPart.AddNewPart<WorksheetPart>(workSheetID);
            WriteDataTableToExcelWorksheet(dt, worksheetPart);

            Sheet sheet = new Sheet() { Name = worksheetName, SheetId = (UInt32Value)worksheetNumber, Id = workSheetID };
            sheets.Append(sheet);

            worksheetNumber++;
        }

        workbook.Append(sheets);
    }

2 个解决方案

#1

Thanks to All, Finally I Got solution of my problem. I just replaced following line of code:

感谢All,最后我解决了我的问题。我刚刚更换了以下代码行:

                    byte[] data1 = new byte[fs1.Length];
                    fs1.Read(data1, 0, data1.Length);
                    fs1.Close();

with this line

用这条线

                    byte[] data1 = fs1.ToArray();

and my problem got resolved.

我的问题得到了解决。

#2

After finishing writing to the memory stream, you need to set back the pointer to its origin before reading it.

完成对内存流的写入后,需要在读取之前将指针设置回原点。

fs1.Seek(0, SeekOrigin.Begin);