Python使用Socket模块实现网络编程的入门指南

import socket

# 1. 创建TCP套接字 SOCK_STREAM代表TCP
server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

# 2. 绑定地址与端口，0.0.0.0代表监听本机所有网卡
HOST = "0.0.0.0"
PORT = 8888
server_socket.bind((HOST, PORT))

# 3. 开启监听，参数为允许等待的最大连接数
server_socket.listen(5)
print(f"服务端启动成功，监听端口：{PORT}")

# 4. 循环等待客户端接入
while True:
    # accept()阻塞，直到有客户端连接
    conn, addr = server_socket.accept()
    print(f"新客户端接入：{addr}")

    # 接收客户端数据，缓冲区大小1024字节
    data = conn.recv(1024)
    if not data:
        conn.close()
        continue
    print("收到客户端消息：", data.decode("utf-8"))

    # 向客户端发送响应
    resp = "服务端已收到你的消息！"
    conn.send(resp.encode("utf-8"))

    # 关闭当前客户端连接
    conn.close()

import socket

# 创建TCP套接字
client_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

# 连接服务端地址
HOST = "127.0.0.1"
PORT = 8888
client_socket.connect((HOST, PORT))

# 发送数据，socket只能传输字节流，字符串需要encode编码
msg = "Hello Socket!"
client_socket.send(msg.encode("utf-8"))

# 接收服务端返回消息
recv_data = client_socket.recv(1024)
print("收到服务端响应：", recv_data.decode("utf-8"))

# 关闭套接字
client_socket.close()

import socket

# SOCK_DGRAM 代表UDP
udp_server = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
udp_server.bind(("0.0.0.0", 9999))
print("UDP服务端启动，端口9999")

while True:
    data, addr = udp_server.recvfrom(1024)
    print(f"来自{addr}消息：{data.decode('utf-8')}")
    udp_server.sendto("UDP收到！".encode("utf-8"), addr)

import socket

udp_client = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
udp_client.sendto("UDP测试消息".encode("utf-8"), ("127.0.0.1", 9999))
data, addr = udp_client.recvfrom(1024)
print("服务端回复：", data.decode("utf-8"))
udp_client.close()