异常处理

  1. class NegativeException(Exception): # 自定义异常
  2.     def __init__(self, x):
  3.         self.x = x 
  5.     def __str__(self):
  6.         return str(self.x) + " is negative."
  8. def divide(x, y):
  9.     try:
  10.         result = x / y
  11.         if x < 0:
  12.             raise NegativeException(x)
  13.     except (ZeroDivisionError,NegativeException) as e: 
  14.         print("ZeroDivisionError:", e)
  15.     except Exception as e:
  16.         print("Exception is:", e)
  17.     else: # 当try执行成功时，会执行else分支
  18.         print("else... result is ", result)
  19.     finally:
  20.         print("finally....")
  22. divide(-1, 2)
  23. # ZeroDivisionError: -1 is negative.
  24. # finally....
  26. divide(2, 0)
  27. # ZeroDivisionError: division by zero
  28. # finally....
  30. divide("2", "1")
  31. # Exception is: unsupported operand type(s) for /: 'str' and 'str'
  32. # finally....

链接：python异常处理