private async Task sendString(Commands.ServerCommands sCom, string str)
{
using (MemoryStream ms = new MemoryStream())
{
//convert object to byte array
byte[] data;
if (str != "")
{
data = Encoding.Unicode.GetBytes(str);
} //get data from string slightly differently than for objects because of encoding
else
{
data = new byte[0];
}
//send command number
byte[] prep = BitConverter.GetBytes(Commands.getServerCommandUInt(sCom));
if (BitConverter.IsLittleEndian) //target computer might use different endian -> send and receive as big endian and if necessary, restore to little endian in client
{
Array.Reverse(prep);
}
await netS.WriteAsync(prep, 0, prep.Length); //write command (uint) to stream
//send data size
prep = BitConverter.GetBytes(data.Length);
if (BitConverter.IsLittleEndian)
{
Array.Reverse(prep);
}
await netS.WriteAsync(prep, 0, prep.Length); //write length of data (int) to stream
//send object
await netS.WriteAsync(data, 0, data.Length); //write object to stream
}
}
private async Task receiveObject(Commands.ServerCommands sCom, int dataSize)
{
MemoryStream ms = new MemoryStream(await receiveData(dataSize));
BinaryFormatter bf = new BinaryFormatter();
ms.Position = 0;
receivedData = bf.Deserialize(ms);
await saveServerCommand(sCom);
}
private async Task awaitServerResponse(Commands.ServerCommands sCom)
{
while (!serverMsgs.Contains(sCom))
{
//Console.WriteLine("Didn't reveive {0} yet ({1}).", sCom, serverMsgs.Contains(sCom));
await Task.Delay(500);
}
//Console.WriteLine("###Received {0}.###", sCom);
}
//information processing, client-server communication
private async Task handleMessage(Commands.ServerCommands sCom, int dataSize)
{
Console.WriteLine("Handling message... {0}, {1}", sCom, dataSize);
//note: this method isn't async, but it wouldn't be able to return async methods if it wasn't declared as one itself
switch (sCom)
{
case Commands.ServerCommands.ValidVersionNumber:
case Commands.ServerCommands.InvalidVersionNumber:
case Commands.ServerCommands.UserAlreadyOnline:
case Commands.ServerCommands.UserNameFound:
case Commands.ServerCommands.UserNameNotFound:
case Commands.ServerCommands.PasswordIncorrect:
case Commands.ServerCommands.LoginSuccessful:
case Commands.ServerCommands.AccountCreatedSuccessfully:
case Commands.ServerCommands.ServerError:
case Commands.ServerCommands.MessageSent:
await saveServerCommand(sCom);
Console.WriteLine("Received server command: {0}.", sCom);
return;
case Commands.ServerCommands.ReceiveString:
await receiveString(sCom, dataSize);
Console.WriteLine("Received string.");
return;
case Commands.ServerCommands.ReceiveList_String:
await receiveObject(sCom, dataSize);
Console.WriteLine("Received list of string.");
return;
case Commands.ServerCommands.MessageForwarded:
await receiveObject(sCom, dataSize);
removeServerResponse(sCom);
Console.WriteLine("Received forwarded message.");
myWindow.Dispatcher.BeginInvoke(new ChatMsgAdderDelegate(myWindow.addChatMessage), System.Windows.Threading.DispatcherPriority.Background, (ChatMessage)receivedData);
break;
case Commands.ServerCommands.OnlineUsersChanged:
await receiveObject(sCom, dataSize);
removeServerResponse(sCom);
Console.WriteLine("Received online users.");
//myWindow.updateUserList((List<string>)receivedData);
//foreach (string user in ((List<string>)receivedData)) Console.WriteLine(user);
updateUserList((List <string>)receivedData);
break;
default:
Console.WriteLine("Unhandled server command ({0}).", sCom);
return;
}
}
public async Task sendObject(Commands.ServerCommands sCom, object obj)
{
//see e.g.: https://stackoverflow.com/questions/2316397/sending-and-receiving-custom-objects-using-tcpclient-class-in-c-sharp
using (MemoryStream ms = new MemoryStream())
{
//convert object to byte array
byte[] data;
if (obj != null)
{
BinaryFormatter bf = new BinaryFormatter();
bf.Serialize(ms, obj); //serialise object to memory stream first -> can provide size of data in byte
data = ms.ToArray(); //the object converted to a byte array
}
else
{
data = new byte[0];
}
//send command number
byte[] prep = BitConverter.GetBytes(Commands.getServerCommandUInt(sCom));
if (BitConverter.IsLittleEndian) //target computer might use different endian -> send and receive as big endian and if necessary, restore to little endian in client
{
Array.Reverse(prep);
}
await netS.WriteAsync(prep, 0, prep.Length); //write command (uint) to stream
//send data size
prep = BitConverter.GetBytes(data.Length);
if (BitConverter.IsLittleEndian)
{
Array.Reverse(prep);
}
await netS.WriteAsync(prep, 0, prep.Length); //write length of data (int) to stream
//send object
await netS.WriteAsync(data, 0, data.Length); //write object to stream
}
}
private async Task receiveString(Commands.ServerCommands sCom, int dataSize)
{
receivedData = Encoding.Unicode.GetString(await receiveData(dataSize));
await saveServerCommand(sCom);
}
private void removeServerResponse(Commands.ServerCommands sCom)
{
serverMsgs.Remove(sCom);
}
private bool checkServerResponse(Commands.ServerCommands sCom)
{
return(serverMsgs.Contains(sCom));
}
private async Task saveServerCommand(Commands.ServerCommands sCom)
{
serverMsgs.Add(sCom); /*Console.WriteLine("Saved server command {0}: {1}.", sCom, serverMsgs.Contains(sCom));*/
}
private async Task sendCommand(Commands.ServerCommands sCom)
{
await sendObject(sCom, null);
}
