winsock客户端和服务器通信

Question

对不起，我知道我在过去一天中发布了与同一主题相关的线程，但是我遇到了另一个问题。

server.cpp

/*Server */ 
#define _WIN32_WINNT 0x501 
#include <iostream> 
#include <windows.h> 
#include <winsock2.h> 
#include <ws2tcpip.h> 
using namespace std; 

const int winsock_version = 2; 
#define PORT "3490" 
#define MAX_NUM_CONNECTIONS 10 

int main(void){ 

    WSADATA wsadata; 

    if (WSAStartup(MAKEWORD(winsock_version,0),&wsadata) == 0){ 
     cout<<"-WSAStartup Initialized." << endl; 

     struct addrinfo hints,*res; 
     int sock_fd; 

     memset(&hints,0,sizeof hints); 
     hints.ai_family = AF_UNSPEC; 
     hints.ai_socktype = SOCK_STREAM; 
     hints.ai_flags = AI_PASSIVE; 

     if (getaddrinfo(NULL,PORT,&hints,&res) != 0){ 
      cout<<"-Call to getaddress was unsucceful." << endl; 
     } 

     if((sock_fd = socket(res->ai_family,res->ai_socktype,res->ai_protocol)) == -1){ 
      cout<<"-Unable to Create socket." << endl; 
     } 

     if ((bind(sock_fd, res->ai_addr, res->ai_addrlen)) != -1){ 
      cout<<"-binding successful." << endl; 
     } 

     if ((listen(sock_fd,MAX_NUM_CONNECTIONS)) != -1){ 
      cout<<"-Listening for incoming connections." << endl; 
     } 
     //------------------------------------------------------------- 

     struct sockaddr_storage incming_info; 
     socklen_t sin_size; 
     sin_size = sizeof incming_info; 

     int new_fd; 

     new_fd = accept(sock_fd, (struct sockaddr*)&incming_info,&sin_size); 
     if (new_fd == -1){ 
      cout<<"-Accepting error." << endl; 
     } 
     if(new_fd == INVALID_SOCKET){ 
      cout<<"-INVALID SOCKET ERROR." << endl; 
     } 
     //------------------------------------------------------------- 

     cout<<"Connected?" << endl; 
     char buffer[128]; 
     while(true){ 
      int ret_val; 

      ret_val = recv(new_fd,buffer,sizeof(buffer),0); 
      if(ret_val == -1){ 
       cout<<"Receiving Error." << endl; 
       break; 
      }else if(ret_val == 0){ 
       cout<<"Connection has been closed!." << endl; 
       break; 
      }else if(ret_val > 0){ 
       cout<<"Server: " << buffer<< endl; 
      } 
     } 

     cout<<"-Closing connection" << endl; 
     closesocket(new_fd); 
    }else{ 
     cout<<"-WSAStartup Initialization failed." << endl; 
     if(WSACleanup()!=0){ 
      cout<<"-WSACleanup Successful." << endl; 
     }else{ 
      cout<<"-WSACleanup Failed." << endl; 
     } 
    } 
    return 0; 
} 

client.cpp

/*client*/ 
#define _WIN32_WINNT 0x501 
#include <iostream> 
#include <windows.h> 
#include <winsock2.h> 
#include <ws2tcpip.h> 
using namespace std; 

#define PORT "3490" 
#define SERVER "localhost" 
const int winsockVersion = 2; 


int main(void){ 

    WSADATA wsadata; 
    if ((WSAStartup(MAKEWORD(2,0),&wsadata)) == 0){ 
     cout<<"-WSAStartup Initialized." << endl; 

     struct addrinfo hints, *res; 
     int sockfd; 

     memset(&hints,0,sizeof hints); 
     hints.ai_family = AF_UNSPEC; 
     hints.ai_socktype = SOCK_STREAM; 

     if (getaddrinfo(SERVER,PORT,&hints,&res) != 0){ 
      cout<<"-getaddrinfo unsuccessful." << endl; 
     } 

     if ((sockfd = socket(res->ai_family,res->ai_socktype,res->ai_protocol)) == -1){ 
      cout<<"-Unable to create socket." << endl; 
     } 

     if ((connect(sockfd,res->ai_addr,res->ai_addrlen)) != -1){ 
      cout<<"-Connection Established." << endl; 
     } 

     cout<<"-Client connecting to: " << res->ai_addr << endl; 

     while(true){ 
      char text_buff[128]; 
      cout<<"Enter text: "; 
      cin>>text_buff; 
      if((send(sockfd,text_buff,sizeof(text_buff),0)) != -1){ 
       cout<<"-text_buff sent!." << endl; 
       break; 
      } 
     closesocket(sockfd); 

     } 

    }else{ 
     cout<<"-WSAStartup Initialization failed." << endl; 
     if(WSACleanup()!=0){ 
      cout<<"-WSACleanup Successful." << endl; 
     }else{ 
      cout<<"-WSACleanup Failed." << endl; 
     } 
    } 

    return 0; 
} 

我可以运行服务器和客户端很好，但我只能发送一个字（不能发一个句子出于某种原因）从在服务器控制台上打印出来的客户端，但一旦在服务器控制台上打印出来，就会输出“接收错误”并关闭。

Answer 1

两个问题
是只读取，直到第一空间。你可以使用std :: string。
2. send(sockfd,text_buff,sizeof(text_buff),0)使用strlen(text_buff) + 1而不是sizeof(text_buff)。
如果使用的std :: string，然后尝试

string line; 
send(sockfd, line.c_str(),line.length()+1,0) 

Answer 2

您不能假设对send()的单个调用就足够了（并且对于recv()也是如此）。您需要遍历数据，直到发送/接收完所有数据。另外，你可能不希望总是发送128个字符，而应该发送所需的长度（并且在消息中包含终止符或前缀长度）。

Answer 3

尝试用std :: string和std :: getline替换使用char text_buff的输入。

while(true) 
{ 
    std::string line; 
    std::cout << "Enter text: "; 
    std::getline(cin, line); 
    if(send(sockfd, text_buff.c_str(), text_buff.size(), 0)) != -1) 
    { 
     std::cout << "-text_buff sent!." << std::endl; 
     break; 
    } 
    closesocket(sockfd); 
} 

我不知道你的循环有你似乎只是循环退出第一次成功地发送任何东西。