python入门之简单socket

TCP

Server

from socket import *
HOST = "127.0.0.1"
PORT = 12345
ADDR = (HOST, PORT)

server = socket (AF_INET, SOCK_STREAM)
server.bind (ADDR)
server.listen (5)
print ("start listen...")

client, addr = server.accept ()
print ("accept a connection from %s" % str (addr))
data = client.recv (1024)
if not data:
print ("there is no data")
print ("exit the server process")
exit ()
print ("received a msg from client : %s" % str (data, encoding = "utf-8"))
client.send (bytes ("Server received.", encoding = "utf8"))

client.close ()
exit ()

Client

from socket import *
HOST = "127.0.0.1"
PORT = 12345
ADDR = (HOST, PORT)

client = socket (AF_INET, SOCK_STREAM)
client.connect (ADDR)
client.send (bytes ("hehe", encoding = "utf8"))
data = client.recv (1024)
print ("Receive data : %s" % str (data, encoding = "utf-8"))
print ("close socket")

client.close ()
exit ()

说明：

必须用from socket import *，不能用import socket

使用print ()函数时，可以用 print (“xxx %s” % m_str)格式化输出字符串，也可以用 print (“xxx”, m_str) 连接多个字符串

程序中 addr 是一个tuple，不能在 print 中这样写：

print ("xxx %s" % addr)

，会报错的。可以这样写：

print ("xxx %s" % str (addr))

调用 send () 函数时，必须把要发送的字符串转换成 bytes 格式才能发送。注意在使用 bytes () 函数的时候，编码时写utf8，解码时写utf-8，有一个短横杠的区别。