Question

我有一部分C代码，我试图移植到C＃。

在我的C代码中，我创建一个套接字然后发出一个接收命令。接收命令是

void receive(mysocket, char * command_buffer)
{
    recv(mysocket, command_buffer, COMMAND_BUFFER_SIZE, 0);
}

现在，命令缓冲区返回新值，包括command_buffer[8]是指向字符串的指针。

我真的很困惑如何在.NET中执行此操作，因为.NET Read（）方法特别采用字节而不是char。重要的是我得到了指向字符串的指针。

有什么想法吗？

Answer 1

Socket Send and Receive C#

Socket.Receive方法

Receive方法从绑定的Socket接收数据到缓冲区。方法返回接收的字节数。如果套接字缓冲区为空a 发生了WouldBlock错误。你应该试着收到数据以后。

以下方法尝试将大小字节接收到缓冲区中偏移位置。如果操作持续超过超时它抛出一个异常毫秒。

public static void Receive(Socket socket, byte[] buffer, int offset, int size, int timeout)
{
  int startTickCount = Environment.TickCount;
  int received = 0;  // how many bytes is already received
  do {
    if (Environment.TickCount > startTickCount + timeout)
      throw new Exception("Timeout.");
    try {
      received += socket.Receive(buffer, offset + received, size - received, SocketFlags.None);
    }
    catch (SocketException ex)
    {
      if (ex.SocketErrorCode == SocketError.WouldBlock ||
          ex.SocketErrorCode == SocketError.IOPending ||
          ex.SocketErrorCode == SocketError.NoBufferSpaceAvailable)
      {
        // socket buffer is probably empty, wait and try again
        Thread.Sleep(30);
      }
      else
        throw ex;  // any serious error occurr
    }
  } while (received < size);
}

Call the Receive method using code such this:
[C#]

Socket socket = tcpClient.Client;
byte[] buffer = new byte[12];  // length of the text "Hello world!"
try
{ // receive data with timeout 10s
  SocketEx.Receive(socket, buffer, 0, buffer.Length, 10000);
  string str = Encoding.UTF8.GetString(buffer, 0, buffer.Length);
}
catch (Exception ex) { /* ... */ }

Answer 2

C＃区分字节数组和Unicode字符串。字节是无符号的8位整数，而char是Unicode字符。它们不可互换。

相当于recv是Socket.Receive。您以托管字节数组的形式分配内存，并将其传递给Receive方法，该方法将使用接收的字节填充数组。没有涉及指针（只是对象引用）。

Socket mysocket = // ...;

byte[] commandBuffer = new byte[8];
socket.Receive(commandBuffer);

.NET相当于recv？

2 个答案: