Extract data from a PubSubBuffer

public void ExtractFromBuffer(byte[] data)
{
    // Initialize a PubSubBuffer.
    var buffer = new PubSubBuffer();
    var size = data.Length;
    var ptr = Marshal.AllocHGlobal(size);
    try
    {
        // Copy the byte array into the created PubSubBuffer.
        Marshal.Copy(data, 0, ptr, data.Length);
        buffer.SetBuffer(ptr, size, size);
        buffer.RewindBuffer();
        if (buffer.MoreItemsToRead() == true)
        {
            // Read each value in the same order than they were written.
            // Read the enumeration value as a System.Byte, and then cast it to the enumeration type.
            Byte msgType;
            buffer.Read(out msgType);
            var dalPSMsgType = (DALPSMessageType)msgType;
            Console.WriteLine("DALPSMessageType: " + dalPSMsgType);

            // Read String value
            String topic;
            buffer.Read(out topic);
            Console.WriteLine("Topic: " + topic);

            // Read Boolean value.
            Boolean boolValue;
            buffer.Read(out boolValue);
            Console.WriteLine("PubSubHeaderData: " + boolValue);

            // Read Int32 value.
            Int32 psBufferLength;
            buffer.Read(out psBufferLength);
            Console.WriteLine("Internal buffer Length: " + psBufferLength);

            // Create a new PubSubBuffer to read the latest item written.
            var psBuffer = new PubSubBuffer();
            if (psBufferLength != 0)
            {
                // Read the PubSubBuffer.
                var bufferData = new byte[psBufferLength];
                buffer.ReadBlob(out bufferData);
                var ptrToInnerBuffer = Marshal.AllocHGlobal(psBufferLength);
                Marshal.Copy(bufferData, 0, ptrToInnerBuffer, psBufferLength);
                psBuffer.SetBuffer(ptrToInnerBuffer, psBufferLength, psBufferLength);
                psBuffer.RewindBuffer();
            }
        }
        else
        {
            Console.WriteLine("Buffer is not initialized.");
        }
    }
    catch (Exception exception)
    {
        throw exception;
    }
    finally
    {
        // Dispose the buffer used to extract all the data and the Marshal pointer.
        buffer.Dispose();
        Marshal.FreeHGlobal(ptr);
    }
}