Question

I am writing a client for a server that typically sends data as strings in 500 or less bytes. However, the data will occasionally exceed that, and a single set of data could contain 200,000 bytes, for all the client knows (on initialization or significant events). However, I would like to not have to have each client running with a 50 MB socket buffer (if it’s even possible).

Each set of data is delimited by a null \0 character. What kind of structure should I look at for storing partially sent data sets?

For example, the server may send ABCDEFGHIJKLMNOPQRSTUV\0WXYZ\0123!\0. I would want to process ABCDEFGHIJKLMNOPQRSTUV, WXYZ, and 123! independently. Also, the server could send ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890LOL123HAHATHISISREALLYLONG without the terminating character. I would want that data set stored somewhere for later appending and processing.

Also, I’m using asynchronous socket methods (BeginSend, EndSend, BeginReceive, EndReceive) if that matters.

Currently I’m debating between List<Byte> and StringBuilder. Any comparison of the two for this situation would be very helpful.

Answer 1

You could just use a List<byte> as your buffer, so the .NET framework takes care of automatically expanding it as needed. When you find a null terminator you can use List.RemoveRange() to remove that message from the buffer and pass it to the next layer up.

You’d probably want to add a check and throw an exception if it exceeds a certain length, rather than just wait until the client runs out of memory.

(This is very similar to Ben S’s answer, but I think a byte array is a bit more robust than a StringBuilder in the face of encoding issues. Decoding bytes to a string is best done higher up, once you have a complete message.)