iTextSharp应用中关于“Cannot access a closed Stream”问题的解决办法（附带提供如何在页面中显示PDF的流）

         private   void  CreatePdf()
         {
            Document doc=new Document();
            MemoryStream ms=new MemoryStream();
            PdfWriter writer =PdfWriter.GetInstance(doc,ms);
            doc.Open();
            doc.Add(new Paragraph(DateTime.Now.ToLongDateString()));
            doc.Close();
            ViewPdf(ms);
        }

         private   void  ViewPdf(Stream fs)
         {
            byte[] buffer=new byte[fs.Length];
            fs.Position=0;            
            fs.Read(buffer,0,(int)fs.Length);
            Response.Clear();
            Response.ContentType = "application/pdf";
            Response.BinaryWrite(buffer);
            Response.OutputStream.Flush();
            Response.OutputStream.Close();
        }

Cannot access a closed Stream.

Line 58:   private void ViewPdf(Stream fs)

Line 59:   {
Line 61:    fs.Position=0;

Line 62:    fs.Read(buffer,0,(int)fs.Length);

     private   void  Page_Load( object  sender, System.EventArgs e)
         {
            //CreatePdf();
            EditPDF();
        }

         private   void  EditPDF()
         {
            PdfReader reader =new PdfReader(@"e:\xml2PDF.pdf");
            MemoryStream ms=new MemoryStream();
            PdfStamper stamper=new PdfStamper(reader,ms);
            stamper.Writer.CloseStream=false;
            PdfContentByte cb=stamper.GetOverContent(1);            
            cb.Circle(250,250,50);
            cb.SetColorFill(iTextSharp.text.Color.RED);
            cb.SetColorStroke(iTextSharp.text.Color.WHITE);
            cb.FillStroke();
            stamper.Close();
            ViewPdf(ms);        
        }

         private   void  CreatePdf()
         {
            Document doc=new Document();
            MemoryStream ms=new MemoryStream();
            PdfWriter writer =PdfWriter.GetInstance(doc,ms);
            writer.CloseStream=false;
            doc.Open();
            doc.Add(new Paragraph(DateTime.Now.ToLongDateString()));
            doc.Close();
            ViewPdf(ms);
        }

         private   void  ViewPdf(Stream fs)
         {
            byte[] buffer=new byte[fs.Length];
            fs.Position=0;            
            fs.Read(buffer,0,(int)fs.Length);
            fs.Close();
            Response.Clear();
            Response.ContentType = "application/pdf";
            Response.BinaryWrite(buffer);
            Response.OutputStream.Flush();
            Response.OutputStream.Close();
        }

如果需要下载而不是在IE中看的话，请把Response.AddHeader("Content-Disposition", "attachment;FileName=out.pdf");前的注释去掉，并替换上你想要的名字。

如果不指定Response.AddHeader("Content-Length",fs.Length.ToString());，IE会把网页内容也输出，在PDF后面，此时显示生成的PDF被破坏（这个说是IE的一个bug，我也不清楚）
如果附件名为中文：
Response.AddHeader("Content-Disposition", "attachment;FileName="+HttpUtility.UrlEncode("中文.pdf"));

内嵌显示PDF
Response.AddHeader("Content-Disposition", "inline;FileName=out.pdf");

更多这方面的信息google上搜索吧。

另外一个和缓存有关的信息，Cache-Control，需要的自己研究下吧。

本文转自RubyPdf 的中文博客博客园博客，原文链接：http://www.cnblogs.com/hardrock/archive/2006/02/23/336397.html，如需转载请自行联系原作http://www.cnblogs.com/hardrock/archive/2006/05/17/402654.html