C#/ TCP/IP write int

[ToneyBoney]

Hello all,

I'm kinda new to the world of C#, so please bear with me. I am trying to write a small application that will write an int to server and then get a reply in the form of a double.

The following is my code to write to the server:

[code=c#]
TcpClient bob = new TcpClient("loca lhost", 61734);
NetworkStream bill = bob.GetStream() ;
BinaryWriter binWriter = new BinaryWriter(bi ll);

Int32 num = 987;
binWriter.Write (num);
binWriter.Close ();
[/code]

However when I read the value in at the server it comes out as -620560384 not 987.

So my question is:
Is this the correct way to write an int over C# TCP/IP sockets?

Also the server code is written in java, does C# do anything weird to bytes before it send them?

Cheers,
Tony.

[Plater]

You might want to check the byte order that gets sent out.
987 in one endian might be 620560384 in the other endian.

[ToneyBoney]

Hey Plater,

Yeah the order in which bytes were sent was the problem. Microsoft being a pack of bastards send all primitive data types in little-endian format whereas my java server (and the rest of the internet) use big-endian.

The following code forces C# sockets to send primitive data types in big-endian format.

Socket socket = new Socket()
NetworkStream stream = new NetworkStream(socket)
BinaryWriter writer = new BinaryWriter(stream)
{
    int myValue = 42;
    writer.Write(IPAddress.HostToNetworkOrder(myValue));
}

edit by mod:
Please use [CODE] tags, not [B] tags for code
--insertAlias

Also as a side note if you want to read in a value in big-endian format, you can use

IPAddress.Netwo rkToHostOrder()

This method doesn't let you read in some primitive data types such as double. So to convert this to big-endian format just use a for loop to assign byte[0] to byte[length -1] and so on and so on. (The byte.Reverse() didn't work for me so I had to do it this way).

[Plater]

Yeah, I figured there had to be a htons function in .NET but wasn't sure of it. I've always manually populated my byte[] for data transfer over sockets, ran in to so many endian issues that I just just did it by hand.

[ToneyBoney]

Ha ha, yeah man I know what you mean. It's almost like microsoft don't want their **** to interop with other systems.

Anyway thanks for the help.

[Curtis Rutland]

Please keep the language clean, ToneyBoney.

MODERATOR

[ToneyBoney]

Yes Mother......... .........

[pvecchio]

So Plater, by doing it manually, do you mean something like this?

byte[] msgPrefix = new byte[8];

msgPrefix[0] = 0;
msgPrefix[1] = 0;
msgPrefix[2] = 0;
msgPrefix[3] = 0x44;
msgPrefix[4] = 0;
msgPrefix[5] = 0x3C;
msgPrefix[6] = 0;
msgPrefix[7] = 0;

Or do I still need to use some sort of code with this:
IPAddress.HostT oNetworkOrder ?

[Plater]

Well I made little functions that handle it, but roughly yes