032網路通信

server下的方法：bind() ,   listen(),  accept(),  recv(),   send(bytes(String)),   sendall(),    
client的方法：connect(),   recv(),    send(),  sendall()

### 建立通信的過程：創建socket，綁定ip和埠，監聽，接收連接socket，用接受到的socket進行通訊。然後才能發送連接數據
server.py

import  socket
sk = socket.socket()    # 創建對象，構造函數裡面的參數，一般都不需要參數
 # family:AF_INET-伺服器之間的通信,AF_UNIX-Unix不同進程之間的通信 type:SOCK_STREAM-TCP連接,SOCK_Dgram-UDP連接
address = ('127.0.0.1',8888)
sk.bind(address)
sk.listen(3)                           # 讓多少個通信進行等待
# print(sk.accept())        # 等待連接，收到的是一個元組，裡面有個 socket對象，以及客戶端的ip和埠
#  (<socket.socketfd=420,family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM,proto=0,laddr=('127.0.0.1',8888),raddr=('127.0.0.1',50510)>, ('127.0.0.1',50510))
conn,addr = sk.accept()                      # 會在這裡阻塞，就是會在這裡等著別人連接   ########註意這裡用的socket對象
conn.send(bytes('不要幻想了','utf8'))     # 不能發送String類型，要發送byte類型

伺服器通過conn.close()關掉通訊
client.py

1 import  socket
2 sk = socket.socket()
3 address = ('127.0.0.1',8888)
4 sk.connect(address)
5 data = sk.recv(1024)
6 print(str(data,'utf8'))

客戶端關閉自己的socket就可以關閉連接

#######通訊改進一#######
每人發一條信息，不能夠停止，停止可以加個判斷
server.py

 1 import  socket
 2 def  get_server_socket():
 3     sk = socket.socket()
 4     server_address = ('127.0.0.1',8888)
 5     sk.bind(server_address)
 6     sk.listen(5)
 7     return  sk
 8 if  __name__ == '__main__':
 9     sk = get_server_socket()
10     print('waiting...')
11     conn,addr = sk.accept()
12     while  True:
13         data = conn.recv(1024)
14         print(str(data,'utf8'))
15         inp = input('>>>')
16         conn.send(bytes(inp,'utf8'))
17         print('waiting...')
18     conn.close()

client.py

 1 import socket
 2 def  connect_server():
 3     sk = socket.socket()
 4     server_address = ('127.0.0.1',8888)
 5     sk.connect(server_address)
 6     return sk
 7 if __name__ == '__main__':
 8     sk = connect_server()
 9     while  True:
10         inp = input('>>>')
11         sk.send(bytes(inp,'utf8'))
12         print('waiting...')
13         data = sk.recv(1024)
14         print(str(data,'utf8'))
15     sk.close()

##########通訊改進二################
客戶端能正常退出
server.py

 1 import  socket
 2 def  get_server_socket():
 3     sk = socket.socket()
 4     server_address = ('127.0.0.1',8888)
 5     sk.bind(server_address)
 6     sk.listen(5)
 7     return sk
 8 if__name__ == '__main__':
 9     sk = get_server_socket()
10     print('waiting...')
11     conn,addr = sk.accept()
12     while  True:
13         data = conn.recv(1024)
14         print(str(data,'utf8'))
15         if not data:
16             print('waitconnect...')
17             conn, addr = sk.accept()
18             continue
19         inp = input('>>>')
20         conn.send(bytes(inp,'utf8'))
21     print('waiting...')
22     conn.close()

client.py

 1 import socket
 2 def  connect_server():
 3     sk = socket.socket()
 4     server_address = ('127.0.0.1',8888)
 5     sk.connect(server_address)
 6     return  sk
 7 if  __name__ == '__main__':
 8     sk = connect_server()
 9     while  True:
10         inp = input('>>>')
11         if  inp == 'exit':
12             break
13         sk.send(bytes(inp,'utf8'))
14         print('waiting...')
15         data = sk.recv(1024)
16         print(str(data,'utf8'))
17 
18 sk.close()

#############通訊改進三#############################
當一個客戶端退出後，能夠接受其他客戶端的信息
server.py

 1 import  socket
 2 def get_server_socket():
 3     sk = socket.socket()
 4     server_address = ('127.0.0.1',8888)
 5     sk.bind(server_address)
 6     sk.listen(5)
 7     return sk
 8 def get_conn(sk):
 9     print('waitconnect...')
10     conn, addr = sk.accept()
11     return conn
12 if __name__ == '__main__':
13     sk = get_server_socket()
14     conn = get_conn(sk)
15     while  True:
16         try:
17             data = conn.recv(1024)
18             ##Linux這裡不會報錯，如果強行關閉了conn，data就會變成空，也就是說Linux的直接不try就行了。
19         except Exception as e:
20             conn = get_conn(sk)
21         print(str(data,'utf8'))
22         if not data:
23             conn = get_conn(sk)
24             continue
25         inp = input('>>>')
26         conn.send(bytes(inp,'utf8'))
27         print('waiting...')
28         conn.close()

client.py

 1 import socket
 2 def  connect_server():
 3     sk = socket.socket()
 4     server_address = ('127.0.0.1',8888)
 5     sk.connect(server_address)
 6     return sk
 7 if __name__  == '__main__':
 8     sk = connect_server()
 9     while True:
10         inp = input('>>>')
11         if inp == 'exit':
12             break
13         sk.send(bytes(inp,'utf8'))
14         print('waiting...')
15         data = sk.recv(1024)
16         print(str(data,'utf8'))
17     sk.close()