套接字io中的while循环答案

【问题标题】：while loop in socket io套接字io中的while循环
【发布时间】：2021-10-29 13:29:52
【问题描述】：

hii 我正在尝试使用 socketio python 构建客户端。捕获事件时如何打破循环

def login():
index = 0
while index == 0:
    username = input("please enter your username\n")
    password = input("please enter your password\n")
    sio.emit('send user name and password', {"username": username, "password": password})

    @sio.on('wrong username')
    def print_message():
        print("this username is not exist")

    @sio.on('wrong password')
    def print_message():
        print("your password is wrong please try again")

    @sio.on('connected')
    def print_message():
        global index
        index = 1
        print("LOGIN OK")

    sio.sleep(2)

【问题讨论】：

标签： python socket.io client python-socketio

【解决方案1】：

您不必将这些函数放在一个循环中。他们会自动捕捉分配给他们的事件：

def login():
    index = 0
    username = input("please enter your username\n")
    password = input("please enter your password\n")
    sio.emit('send user name and password', {"username": username, "password": password})

@sio.on('wrong username')
def print_message():
    print("this username is not exist")

@sio.on('wrong password')
def print_message():
    print("your password is wrong please try again")

@sio.on('connected')
def print_message():
    global index
    index = 1
    print("LOGIN OK")

   # sio.sleep(2)

【讨论】：

但如果用户不存在或密码已磨损，我希望该功能再次询问用户名和密码

【解决方案2】：

Socket.IO 是异步的，您不要将事件处理程序放在 while 循环中。如果您需要将主线程与收到的事件同步，您可以使用Event 对象。像这样的：

login_ok = None
event = threading.Event()

@sio.on('wrong username')
def print_message():
    print("this username is not exist")
    login_ok = False
    event.set()

@sio.on('wrong password')
def print_message():
    print("your password is wrong please try again")
    login_ok = False
    event.set()

@sio.on('connected')
def print_message():
    global index
    index = 1
    print("LOGIN OK")
    login_ok = True
    event.set()

def login():
    index = 0
    while index == 0:
        username = input("please enter your username\n")
        password = input("please enter your password\n")
        sio.emit('send user name and password', {"username": username, "password": password})

        event.wait()
        event.clear()
        if login_ok:
            break

假设您还编写了服务器，您可能要考虑的另一个选项是使用 Socket.IO 的 ACK 功能。您可以将 ACK 响应设置为登录结果，而不是使用单独的事件响应登录。那么你就不必在客户端处理任何事件，只需从事件响应中获取登录结果即可。这是一个例子：

def login():
    index = 0
    while index == 0:
        username = input("please enter your username\n")
        password = input("please enter your password\n")
        response = sio.call('send user name and password', {"username": username, "password": password})
        if response['login_ok']:
            break
        print(response['error'])

要使第二个选项起作用，必须修改您的服务器以发送带有login_ok 和error 的字典作为对登录事件的响应。

【讨论】：