Update Memorystream when replacing Bookmark

Question

Guys, I’m doing a job RESTFUL in C# that has a method that receives a byte array of a document WORD, and in this document I need to replace existing bookmarks with text that are also passed in the method.

• Problem : When performing the replacement of bookmarks by the appropriate text I cannot update the Memorystream to obtain the byte array updated with file modifications. Someone has already had to work with

• Referential

  public class ReferenciaRelatorio
  {
         public string referencia {get; set;}
         public object valor { get; set; }
   }
  

• Reporteriods

   [DataContract]
   public class RelatorioDS
   {        
       [DataMember]
       public List<ReferenciaRelatorio> mapaDeSubstituicao { get; set; }
       /**arquivo binario na base 64**/
      [DataMember]
      public string template { get; set; }
   }
  

• Geradorrelatorioword (EDITED)

  using System;
  using System.IO;
  
  using System.Collections.Generic;
  using System.Linq;
  using System.Web;
  using Microsoft.Office.Interop.Word;
  using DocumentFormat.OpenXml.Packaging;
  using DocumentFormat.OpenXml.Wordprocessing;
  using DocumentFormat.OpenXml;
  
  
  
  namespace RestService
  {
  public class GeradorRelatorioWord 
  {
  
     public ResponseData gerarRelatorio(RelatorioDS data)
     {
        ResponseData resposta =  new ResponseData();
        try
        {
           byte[] saida = null;
           byte[] template = System.Convert.FromBase64String(data.template);
           using (MemoryStream mem = new MemoryStream(template))
           {
              /**EDITADO**/
              /**mem.Write(template, 0, (int)template.Length);**/
             using (WordprocessingDocument wordDoc = WordprocessingDocument.Open(mem, false))
             {
               var bookMarks = recuperarBookMark(wordDoc.MainDocumentPart.Document);
               substituirBookMark(data, bookMarks);
               byte[] buf;  
               Stream stream = wordDoc.MainDocumentPart.GetStream();
               buf = new byte[stream.Length];  
               stream.Read(buf, 0, buf.Length);
               saida = buf ;
  
  
               /** EDITADO **/
               /**
               wordDoc.MainDocumentPart.Document.Save();
               wordDoc.Close();
               using (StreamReader sr = new StreamReader(wordDoc.MainDocumentPart.GetStream()))
               {
                 string documentoTexto = sr.ReadToEnd();
  
                 using (StreamWriter sw = new StreamWriter(wordDoc.MainDocumentPart.GetStream(FileMode.Create)))
                 {
                   sw.Write(documentoTexto);
  
                   MemoryStream me = new MemoryStream();
                   sw.BaseStream.CopyTo(me);
                   saida = me.ToArray();
                 }
  
  
               }**/
  
             }
             resposta.relatorio = System.Convert.ToBase64String(saida);
  
           }
      }
      catch(Exception e)
      {
  
        resposta.erros.Add(new MensagemErro(e));
  
      }
      return resposta;
     }
  
     /**
     * Recupera os BookMarks que existirem
     **/
     private Dictionary<string, BookmarkEnd> recuperarBookMark(OpenXmlElement documentPart, Dictionary<string, BookmarkEnd> results = null, Dictionary<string, string> unmatched = null)
     {
        results = results ?? new Dictionary<string, BookmarkEnd>();
        unmatched = unmatched ?? new Dictionary<string, string>();
  
        foreach (var child in documentPart.Elements())
        {
            if (child is BookmarkStart)
            {
              var bStart = child as BookmarkStart;
              unmatched.Add(bStart.Id, bStart.Name);
            }
  
            if (child is BookmarkEnd)
            {
              var bEnd = child as BookmarkEnd;
              foreach (var orphanName in unmatched)
              {
               if (bEnd.Id == orphanName.Key)
               results.Add(orphanName.Value, bEnd);
              }
            }
  
            recuperarBookMark(child, results, unmatched);
        }
  
        return results;
     }
  
     /**
     * substitui os bookmarks
     *
     *
     **/
     private static void substituirBookMark(RelatorioDS data, Dictionary<string, BookmarkEnd> bookMarks)
     {
        foreach (var end in bookMarks)
        {
          string bookmark = Uri.UnescapeDataString(end.Key);
          foreach (ReferenciaRelatorio entry in data.mapaDeSubstituicao)
          {
            if (bookmark.Equals(entry.referencia))
            {
              var textElement = new Text((string)entry.valor);
              var runElement = new Run(textElement);
  
              end.Value.InsertAfterSelf(runElement);
            }
  
          }
  
        }
     }
  
  
  }
  }
  

Answer 1

Your code dealing with the stream has some problems:

First: when you write on stream mem the stream cursor is at the end of the stream, which can cause your reading to fail. Tip: change the code snippet

byte[] template = System.Convert.FromBase64String(data.template);
using (MemoryStream mem = new MemoryStream())
{
    mem.Write(template, 0, (int)template.Length);
    using (WordprocessingDocument wordDoc = WordprocessingDocument.Open(mem, true))

for

byte[] template = System.Convert.FromBase64String(data.template);
using (MemoryStream mem = new MemoryStream(template))
{
    using (WordprocessingDocument wordDoc = WordprocessingDocument.Open(mem, false))

Second: the word document stream is not necessarily text; use a StreamReader and converting to text (using UTF-8 or other default encoding) will likely cause data loss. Swap the snippet

using (StreamReader sr = new StreamReader(wordDoc.MainDocumentPart.GetStream()))
{
    string documentoTexto = sr.ReadToEnd();
    using (StreamWriter sw = new StreamWriter(wordDoc.MainDocumentPart.GetStream(FileMode.Create)))
    {
        sw.Write(documentoTexto);
        MemoryStream me = new MemoryStream();
        sw.BaseStream.CopyTo(me);
        saida = me.ToArray();
    }
}

for

using (var mem = new MemoryStream()) {
    wordDoc.MainDocumentPart.GetStream().ToArray().CopyTo(mem);
    saida = mem.ToArray();
}