c# - how to send binary data within an xml string

Question

I want to send a binary file to .net c# component in the following xml format

<BinaryFileString fileType='pdf'>
    <!--binary file data string here-->
</BinaryFileString>

In the called component I will use the above xml string and convert the binary string received within the BinaryFileString tag, into a file as specified by the filetype='' attribute. The file type could be doc/pdf/xls/rtf

I have the code in the calling application to get out the bytes from the file to be sent. How do I prepare it to be sent with xml tags wrapped around it? I want the application to send out a string to the component and not a byte stream. This is because there is no way I can decipher the file type [pdf/doc/xls] just by looking at the byte stream. Hence the xml string with the filetype attribute. Any ideas on this?

method for extracting Bytes below

   FileStream fs = new FileStream(_filePath, FileMode.Open, FileAccess.Read);
   using (Stream input = fs)
   {
      byte[] buffer = new byte[8192];
      int bytesRead;
      while ((bytesRead = input.Read(buffer, 0, buffer.Length)) > 0)
      {}
   }
   return buffer;

Thanks.

Edit:

Just to clarify why I am using an xml string rather than setting properties on my component. Actually my calling app is trying to simulate how Siebel will call my component. http://download.oracle.com/docs/cd/E05553_01/books/eScript/eScript_JSReference244.html#wp1014380 Im not sure if Siebel can set my components properties as I need it to. So Im working on the angle of it sending the data in xml.

Answer 1

Base64 representation is universaly used to represent binary data.

public void EncodeWithString() {
    System.IO.FileStream inFile;     
    byte[] binaryData;

    try {
        inFile = new System.IO.FileStream(inputFileName,
                                          System.IO.FileMode.Open,
                                          System.IO.FileAccess.Read);
        binaryData = new Byte[inFile.Length];
        long bytesRead = inFile.Read(binaryData, 0,
                                    (int)inFile.Length);
        inFile.Close();
    }
    catch (System.Exception exp) {
        // Error creating stream or reading from it.
        System.Console.WriteLine("{0}", exp.Message);
        return;
    }

    // Convert the binary input into Base64 UUEncoded output.
    string base64String;
    try {
         base64String = 
            System.Convert.ToBase64String(binaryData, 
                                          0,
                                          binaryData.Length);
    }
    catch (System.ArgumentNullException) {
        System.Console.WriteLine("Binary data array is null.");
        return;
    }

    // Write the UUEncoded version to the XML file.
    System.IO.StreamWriter outFile; 
    try {
        outFile = new System.IO.StreamWriter(outputFileName,
                                    false,
                                    System.Text.Encoding.ASCII);             
        outFile.Write("<BinaryFileString fileType='pdf'>");
        outFile.Write(base64String);
        outFile.Write("</BinaryFileString>");
        outFile.Close();
    }
    catch (System.Exception exp) {
        // Error creating stream or writing to it.
        System.Console.WriteLine("{0}", exp.Message);
    }
}

At the receiving end you can reverse this and get back original file content as mentioned below.

        // Convert the Base64 UUEncoded input into binary output.
        byte[] binaryData;
        try {
            binaryData = 
                System.Convert.FromBase64String(base64String);
        }
        catch (System.ArgumentNullException) {
            System.Console.WriteLine("Base 64 string is null.");
            return;
        }
        catch (System.FormatException) {
            System.Console.WriteLine("Base 64 string length is not " +
                "4 or is not an even multiple of 4." );
            return;
        }