UDP不像TCP,無需在連接狀態下交換數據,因此基於UDP的服務器端和客戶端無需建立連接過程。也就是說,無需調用listen()函數和accept()函數。UDP中只有創建套接字的過程和數據交換的過程。
運行結果:
源代碼:
服務器端:
#include <stdio.h>
#include <WinSock2.h>
#pragma comment(lib, "ws2_32.lib") //加載ws2_32.dll
const int BUFSIZE = 100;
int main()
{
WSADATA wsaData;
WSAStartup(MAKEWORD(2, 2), &wsaData);
//創建套接字
SOCKET servSock = socket(AF_INET, SOCK_DGRAM, 0);
//綁定套接字
sockaddr_in servAddr;
//每個字節都用0填充
memset(&servAddr, 0, sizeof(servAddr));
//使用IPv4地址
servAddr.sin_family = AF_INET;
//自動獲取IP地址
servAddr.sin_addr.s_addr = htonl(INADDR_ANY);
//端口
servAddr.sin_port = htons(1234);
bind(servSock, (sockaddr *)&servSock, sizeof(servSock));
//接收客戶端請求
//客戶端地址信息
sockaddr clntAddr;
int nSize = sizeof(sockaddr);
//緩衝區
char buffer[BUFSIZE] = {0};
while(true)
{
int strLen = recvfrom(servSock, buffer, BUFSIZE, 0, &clntAddr, &nSize);
sendto(servSock, buffer, strLen, 0, &clntAddr, nSize);
}
closesocket(servSock);
WSACleanup();
return 0;
}
客戶端:
#include <stdio.h>
#include <WinSock2.h>
#pragma comment(lib, "ws2_32.lib") //加載ws2_32.dll
const int BUFSIZE = 100;
int main()
{
//初始化DLL
WSADATA wsaData;
WSAStartup(MAKEWORD(2,2), &wsaData);
//創建套接字
SOCKET servSock = socket(AF_INET, SOCK_DGRAM, 0);
//服務器地址信息
sockaddr_in servAddr;
//每個字節都用0填充
memset(&servAddr, 0, sizeof(servAddr));
servAddr.sin_family = AF_INET;
servAddr.sin_addr.s_addr = inet_addr("127.0.0.1");
servAddr.sin_port = htons(1234);
char buffer[BUFSIZE] = {0};
sockaddr fromAddr;
int nSize = sizeof(sockaddr);
//不斷獲取用戶輸入併發送給服務器,然後接收服務器數據
while(true)
{
printf("Input a string: ");
gets(buffer);
sendto(servSock, buffer, strlen(buffer), 0, (sockaddr *)&servAddr, sizeof(servAddr));
int strLen = recvfrom(servSock, buffer, BUFSIZE, 0, &fromAddr, &nSize);
printf("Message form server: %s\n", buffer);
memset(buffer, 0, sizeof(buffer));
}
closesocket(servSock);
system("pause");
return 0;
}