CODEWITHSUNDEEP
c#
Nick
Nick

Reputation: 898

C# How to correctly save a binary image file from database?

I am trying to export employee images from a database, save them onto my computer, then upload them to Salesforce in each employee's account. My problem is that there must be an issue with the way that I am saving the files from the database. When I go to upload to Salesforce the picture file pulled from the database, it tells me "your file cannot be uploaded at this time. please try again in a few minutes". However, when I email an individual picture to myself, download it, then upload that picture, it works. (I tried to do this en masse; it did not work). I have come to the conclusion that the issue might be with the code. The photo is stored as varbinary(max) and saved as both .png and .jpeg types, and extracted from the database using a variation of MSDN's code:

   SqlConnection connection = new SqlConnection(connectionString);
   SqlCommand command = new SqlCommand(queryString, connection);

   connection.Open();
   SqlDataReader myReader = command.ExecuteReader(CommandBehavior.SequentialAccess);

   while (myReader.Read())
   {
      filePath = @"C:\Users\npredey\Documents\Photos_from_database\" + myReader["first_name"] + '_' + myReader["last_name"];
      FileStream fs = new FileStream(filePath + ".gif", FileMode.OpenOrCreate, FileAccess.Write); // creates a new file for output

      bw = new BinaryWriter(fs);

      startIndex = 0;
      retval = myReader.GetBytes(3, startIndex, outbyte, 0, bufferSize);

      while (retval == bufferSize)
      {
         bw.Write(outbyte);
         bw.Flush();

         startIndex += bufferSize;
         retval = myReader.GetBytes(3, startIndex, outbyte, 0, bufferSize);
      }

      bw.Write(outbyte, 0, (int)retval - 1);
      bw.Flush();

      bw.Close();
      fs.Close();
   }
   myReader.Close();
   connection.Close();

Could there be an issue with how the file is saved, where it would not be able to be uploaded? I have saved the file with all three acceptable extensions (.gif, .jpg, .png) and none of them have worked.

Upvotes: 0

Views: 796

Answers (1)

Shago
Shago

Reputation: 605

On last write you shouldn't substract 1 from retval.

retval contains the numbers of bytes read. The third parameters of BinaryWriter.Write is the numbers of bytes to write.

As you want to write all bytes you should only pass retval instead of retval - 1, which would keep the last byte from beign written.

Upvotes: 1

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