除了之后如何继续？

Question

我在范围内循环以检查给定 IP 输入中的所有端口是否打开，或者某些端口套接字库无法识别它，所以它给我一个找不到端口的错误，

所以我使用 try 和 except 来更改错误代码，但我无法继续到下一个端口，脚本停止并且无法使用 continue with except 跳过该端口并检查下一个端口。

def all_ports():
    target = input('Type The IP : ')
    
    try:
        for port in range(1 , 65,536):
            s = socket.socket(socket.AF_INET , socket.SOCK_STREAM)
            s.settimeout(1)
            r = s.connect_ex((target , port))

            if r == 0:
                service = socket.getservbyport(port)
                print(f'{port} is open !!!!!!!! ,  and service is {service}')
            else:
                service = socket.getservbyport(port)
                print(f'{port} is closed !!!! and service is {service}')
                s.close()
    except:
       print(f'we dont have port {port} in our system !')

Answer 1

您可以更改 for 和 try 的顺序，以仅围绕一个套接字连接而不是所有套接字连接进行异常处理，然后您的代码可以在一个套接字连接失败时恢复端口

def all_ports():
    target = input('Type The IP : ')
    for port in range(1, 65536):
        try:
            s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            s.settimeout(1)
            r = s.connect_ex((target, port))
            service = socket.getservbyport(port)
            if r == 0:
                print(f'{port} is open !!!!!!!! ,  and service is {service}')
            else:
                print(f'{port} is closed !!!! and service is {service}')
            s.close()
        except:
            print(f'We dont have port {port} in our system !')

Answer 2

我会通过简单地将 try 和 except 块放在 for 循环中来解决这个问题。

为简单起见，这里有一个针对这两种情况的简单示例：

不起作用

item_list = [1, 2, 3, "a", 5]

try:
    for item in item_list:
        item += 1  # will give error for "a" as it is not a number
        print("item is:", item)
except:
    print("wrong input")

输出：

item is: 2
item is: 3
item is: 4
wrong input

解决这个问题：

有效

for item in item_list:
    try:
        item += 1
        print("item is:", item) 
    except:
        print("wrong input")

输出：

item is: 2
item is: 3
item is: 4
wrong input
item is: 6

除了之后如何继续？

How to continue after except?

python

networking

backend