python异常处理

try 后面写正常运行的程序代码，except即为异常情况

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a = 0 b = 10 try:     c = b / int(a)     print(c) except:      print("error")

　　

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a = 0 b = 10 try:     c = b / int(a)     print(c) except Exception as e:     print('Exception')     print(e)

　

• try ....except...else 语句，当没有异常发生时，else中的语句将会被执行；发生异常时，else的语句没有被运行
• 当执行try ...finally 语句时，无论异常是否发生，在程序结束前，finally中的语句都会被执行。

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a = input("a=")# 输入：0或- b = 10 try:     c = b / int(a)     print(c) except ZeroDivisionError as e:     print('ZeroDivisionError')     print(e) except ValueError as e:     print('ValueError')     print(e) except Exception as e:     print('Exception')     print(e) else:#不出现异常，就执行本语句     print("else") finally:#不管是否有异常，都会执行本句     print('finally')

　　

raise引发一个异常，比如，当一个条件不满足用户意愿时引发一个异常

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a=3 if a<4:     raise Exception else: print(a)

 

 

参考： 

https://edu.hellobi.com/course/234/play/lesson/3977

https://www.cnblogs.com/bokeyuan11/p/9146607.html