This is a followup to my last question.

I now have a byte[] of values for my bitmap image. Eventually I will be passing a string to the print spooler of the format String.Format("GW{0},{1},{2},{3},", X, Y, stride, _Bitmap.Height) + my binary data; I am using the SendBytesToPrinter command from here.

Here is my code so far to send it to the printer

public static bool SendStringPlusByteBlockToPrinter(string szPrinterName, string szString, byte[] bytes)
{
    IntPtr pBytes;
    Int32 dwCount;
    // How many characters are in the string?
    dwCount = szString.Length;
    // Assume that the printer is expecting ANSI text, and then convert
    // the string to ANSI text.
    pBytes = Marshal.StringToCoTaskMemAnsi(szString);
    pBytes = Marshal.ReAllocCoTaskMem(pBytes, szString.Length + bytes.Length);
    Marshal.Copy(bytes,0, SOMTHING GOES HERE,bytes.Length); // this is the problem line
    // Send the converted ANSI string + the concatenated bytes to the printer.
    SendBytesToPrinter(szPrinterName, pBytes, dwCount);
    Marshal.FreeCoTaskMem(pBytes);
    return true;
}

My issue is I do not know how to make my data appended on to the end of the string. Any help would be greatly appreciated, and if I am doing this totally wrong I am fine in going a entirely different way (for example somehow getting the binary data concatenated on to the string before the move to unmanaged space.

P.S. As a second question, will ReAllocCoTaskMem move the data that is sitting in it before the call to the new location?