C# Can'；t将PDF文件从MemoryStream复制到FileStream

我做错什么了吗？请问为什么我不能打开保存的两个PDF文件

至于MemoryStream，它被保存到我的目录->从Chrome下载文件夹 对于FileStream，它保存到我在代码中指定的文件路径

谢谢你的帮助。多谢各位

代码：

protected void BTN_Assign_Click(object sender, EventArgs e)
    {
        //String id = DDL_PatientID.SelectedItem.ToString();
        String id = TB_PatientID.Text;
        String name = TB_PatientName.Text;
        String bedID = DDL_BedID.SelectedItem.ToString();
        String classType = DDL_Class.SelectedItem.ToString();
        String block = TB_Block.Text;
        String level = TB_Level.Text;
        String staffId = DDL_StaffID.SelectedItem.ToString();
        DateTime dt = DateTime.Now;
        String dtAssign = dt.ToString("dd MMM yyyy h:mm tt");

        int result = 0;

        //Assigning bed (In Beds Table)
        /*BedsBLL add = new BedsBLL();
        result = add.assignBed(bedID, id, name, classType, block, level, staffId, dtAssign);*/

        //Updating status of Bed Selected (In BedsList Table)
        String status = "Alloted";
        BedsBLL update = new BedsBLL();
        result = update.updateBedStatusToAlloted(status, bedID, id, name, staffId, dtAssign);

        AdmissionBLL a = new AdmissionBLL();
        int assignCounter = 0;
        assignCounter = a.updateBedAssignedAdmission(id, bedID);

        //PDF Creation with Admission Details from previous page
        // --- START ---

        DataTable admissionDetails = new DataTable();
        admissionDetails.Columns.Add("Date & Time Admitted");
        admissionDetails.Columns.Add("Reason");
        admissionDetails.Columns.Add("Family Phone");
        admissionDetails.Columns.Add("Family Email");
        admissionDetails.Columns.Add("First Time Admitted");

        DataRow dr;
        dr = admissionDetails.NewRow();
        dr["Date & Time Admitted"] = Session["DTAdmitted"].ToString();
        dr["Reason"] = Session["Reason"].ToString();
        dr["Family Phone"] = Session["FamilyPhone"].ToString();
        dr["Family Email"] = Session["FamilyEmail"].ToString();
        dr["First Time Admitted"] = Session["FirstTimeAdmitted"].ToString();
        admissionDetails.Rows.Add(dr);

        Document pdfDocument = new Document(PageSize.A4, 40f, 40f, 40f, 40f);
        Font NormalFont = FontFactory.GetFont("Arial", 8, Font.NORMAL, BaseColor.BLACK);
        Font BoldFontForHeader = FontFactory.GetFont("Arial", 10, Font.BOLD, BaseColor.BLACK);

        String fileName = @"C:\Users\Dom\Downloads\WebFormApplication\WebFormApplication\WebFormApplication\Exported Documents\" + Session["PatientID"].ToString() + " Admission PDF" + ".pdf";

        Directory.CreateDirectory(Path.GetDirectoryName(fileName));

        PdfPCell cell = null;

        using (MemoryStream ms = new MemoryStream())
        {
            PdfWriter writer = PdfWriter.GetInstance(pdfDocument, ms);

            FileStream fs = new FileStream(fileName, FileMode.Create);

            //Admission Record
            PdfPTable admissionTable = new PdfPTable(admissionDetails.Columns.Count);
            admissionTable.TotalWidth = 550f;
            admissionTable.LockedWidth = true;
            admissionTable.HorizontalAlignment = Element.ALIGN_CENTER;
            admissionTable.SetWidths(new float[] { 0.35f, 0.35f, 0.35f, 0.35f, 0.35f });
            admissionTable.SpacingBefore = 30f;

            string[] headersName = { "Date Time Admitted", "Reason", "Family Phone", "Family Email", "First Time Admitted" };

            for (int i = 0; i < headersName.Length; i++)
            {
                PdfPCell hCell = new PdfPCell(new Phrase(headersName[i].ToString(), BoldFontForHeader));
                admissionTable.AddCell(hCell);
            }

            foreach (DataRow row in admissionDetails.Rows)
            {
                foreach (object tableCell in row.ItemArray)
                {
                    cell = new PdfPCell(new Phrase(tableCell.ToString()));
                    cell.Padding = 5;
                    admissionTable.AddCell(cell);
                }
            }

            //Beds Record
            PdfPTable bedsRecord = new PdfPTable(5);
            bedsRecord.TotalWidth = 550f;
            bedsRecord.LockedWidth = true;
            bedsRecord.HorizontalAlignment = Element.ALIGN_CENTER;
            bedsRecord.SetWidths(new float[] { 0.35f, 0.35f, 0.35f, 0.35f, 0.35f });
            bedsRecord.SpacingBefore = 30f;

            string[] headersNameBed = { "Bed ID", "Class", "Block", "Level", "Staff Incharge ID" };

            for (int i = 0; i < headersNameBed.Length; i++)
            {
                PdfPCell hCell = new PdfPCell(new Phrase(headersNameBed[i].ToString(), BoldFontForHeader));
                bedsRecord.AddCell(hCell);
            }

            PdfPCell[] cells = new PdfPCell[] {
                new PdfPCell(new Phrase(bedID.ToString())),
                new PdfPCell(new Phrase(classType.ToString())),
                new PdfPCell(new Phrase(block.ToString())),
                new PdfPCell(new Phrase(level.ToString())),
                new PdfPCell(new Phrase(staffId.ToString()))
            };

            PdfPRow bRow = new PdfPRow(cells);
            bedsRecord.Rows.Add(bRow);

            pdfDocument.Open();

            //Top of Document

            Paragraph p1 = new Paragraph("Mount Olympus Hospital", new Font(Font.FontFamily.HELVETICA, 18));
            Paragraph p2 = new Paragraph("24 Jalan Kapal Street 42 Singapore 554524", new Font(Font.FontFamily.HELVETICA, 12));
            Paragraph p3 = new Paragraph("Telephone: 6550-9514 Fax: 6550-9245", new Font(Font.FontFamily.HELVETICA, 12));

            p1.Alignment = Element.ALIGN_CENTER;
            p2.Alignment = Element.ALIGN_CENTER;
            p3.Alignment = Element.ALIGN_CENTER;

            pdfDocument.Add(p1);
            pdfDocument.Add(p2);
            pdfDocument.Add(p3);

            Paragraph p4 = new Paragraph("Patient ID: " + Session["PatientID"], new Font(Font.FontFamily.TIMES_ROMAN, 11));
            Paragraph p5 = new Paragraph("Patient Name: " + Session["PatientName"], new Font(Font.FontFamily.TIMES_ROMAN, 11));

            p4.SpacingBefore = 20f;
            p4.Alignment = Element.ALIGN_LEFT;
            p5.Alignment = Element.ALIGN_LEFT;
            p5.SpacingAfter = 20f;

            pdfDocument.Add(p4);
            pdfDocument.Add(p5);

            Paragraph p6 = new Paragraph("Admission Details", new Font(Font.FontFamily.HELVETICA, 16));
            p6.Alignment = Element.ALIGN_LEFT;
            p6.SpacingBefore = 20f;

            pdfDocument.Add(p6);

            pdfDocument.Add(admissionTable);

            Paragraph p7 = new Paragraph("Bed Details", new Font(Font.FontFamily.HELVETICA, 16));
            p7.Alignment = Element.ALIGN_LEFT;
            p7.SpacingBefore = 20f;

            pdfDocument.Add(p7);

            pdfDocument.Add(bedsRecord);

            byte[] bytes = ms.ToArray();
            ms.Position = 0;
            ms.CopyTo(fs);
            fs.CopyTo(ms);

            pdfDocument.Close();



            ms.Close();
            fs.Close();
            Response.Clear();
            Response.ContentType = "application/pdf";
            Response.AddHeader("content-disposition", "attachment;filename=" + Session["PatientID"].ToString() + " Admission PDF" + ".pdf");
            Response.ContentType = "application/pdf";
            Response.Buffer = true;
            Response.Cache.SetCacheability(HttpCacheability.NoCache);
            Response.BinaryWrite(bytes);
            Response.End();
            Response.Close();
        }

        /*using (System.IO.FileStream fs = new System.IO.FileStream())
        {

        }*/



        // --- END ---

        //Showing succcesful panel.
        if (result > 0 && assignCounter > 0)
        {
            Panel_ErrorMsg.Visible = true;
            //Panel_ErrorMsg.ToolTip = "Click on the button to return to Beds List";
            lb_ErrorMsg.Text = "Successfully assigned bed to Patient " + name 
                + " and updated Bed " + bedID + " status to Alloted.";
            BTN_Assign.Visible = false;
        }
    }

受保护的无效BTN\u分配\u单击（对象发送方，事件参数e）
{
//字符串id=DDL_PatientID.SelectedItem.ToString（）；
字符串id=TB_PatientID.Text；
字符串名称=TB_PatientName.Text；
字符串bedID=DDL_bedID.SelectedItem.ToString（）；
String classType=DDL_Class.SelectedItem.ToString（）；
String block=TB_block.Text；
字符串级别=TB_level.Text；
字符串staffId=DDL_staffId.SelectedItem.ToString（）；
DateTime dt=DateTime.Now；
字符串dtAssign=dt.ToString（“dd-MMM-yyy-h:mm-tt”）；
int结果=0；
//分配床位（床位表中）
/*BEDBBLL add=新BEDBBLL（）；
结果=add.assignBed（bedID，id，name，classType，block，level，staffId，dtAssign）*/
//更新所选床位的状态（在床位列表表中）
字符串状态=“已分配”；
BEDBBLL update=新BEDBBLL（）；
结果=update.updateBedStatusToAlloted（状态、bedID、id、名称、staffId、dtAssign）；
AdmissionBLL a=新的AdmissionBLL（）；
int赋值计数器=0；
assignCounter=a.UpdateBedAssignedMission（id，bedID）；
//使用上一页中的准入详细信息创建PDF
//---开始---
DataTable admissionDetails=新DataTable（）；
录取详情。栏。添加（“录取日期和时间”）；
允许详情。列。添加（“原因”）；
允许详细信息。列。添加（“家庭电话”）；
允许详细信息。列。添加（“家庭电子邮件”）；
录取详情。栏。添加（“首次录取”）；
数据行dr；
dr=许可详情。NewRow（）；
dr[“允许的日期和时间”]=会话[“允许的数据”].ToString（）；
dr[“Reason”]=会话[“Reason”].ToString（）；
dr[“家庭电话”]=会话[“家庭电话”]。ToString（）；
dr[“家庭电子邮件”]=会话[“家庭邮件”].ToString（）；
dr[“首次接纳”]=会话[“首次接纳”].ToString（）；
允许详细信息。行。添加（dr）；
文档pdfDocument=新文档（PageSize.A4、40f、40f、40f、40f）；
Font-NormalFont=FontFactory.GetFont（“Arial”，8，Font.NORMAL，BaseColor.BLACK）；
Font BoldFontForHeader=FontFactory.GetFont（“Arial”，10，Font.BOLD，BASECLOR.BLACK）；
字符串文件名=@“C:\Users\Dom\Downloads\WebFormApplication\WebFormApplication\WebFormApplication\Exported Documents\”+会话[“PatientID”].ToString（）+“Admission PDF”+“.PDF”；
CreateDirectory（Path.GetDirectoryName（fileName））；
PdfPCell=null；
使用（MemoryStream ms=new MemoryStream（））
{
PdfWriter writer=PdfWriter.GetInstance（pdfDocument，ms）；
FileStream fs=newfilestream（文件名，FileMode.Create）；
//录取记录
PdfPTable admissionTable=新的PdfPTable（admissionDetails.Columns.Count）；
容许总宽度=550f；
admissionTable.LockedWidth=true；
admissionTable.HorizontalAlignment=Element.ALIGN\u CENTER；
可接受的设置宽度（新浮动[]{0.35f，0.35f，0.35f，0.35f，0.35f}）；
容许表.SpacingBefore=30f；
字符串[]headersName={“入院日期时间”、“原因”、“家庭电话”、“家庭电子邮件”、“首次入院”}；
for（int i=0；i        pdfDocument.Close();

        ms.Position = 0;
        ms.CopyTo(fs);

                pdfDocument.Close();
                //ms.Position = 0;
                //ms.CopyTo(fs);
                //fs.CopyTo(ms);

                byte[] bytes = ms.ToArray();

                using (FileStream fs = new FileStream(fileName, FileMode.Create))
                {
                    ms.Position = 0;
                    ms.CopyTo(fs);
                }