python中常见的异常类型

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Python中常见的错误类型：

  • NameError：尝试访问一个未申明的变量
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>>> v
NameError: name 'v' is not defined
  • ZeroDivisionError：除数为0
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>>> v = 1/0
ZeroDivisionError: int division or modulo by zero
  • SyntaxError：语法错误
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int int
SyntaxError: invalid syntax (<pyshell#14>, line 1)
  • IndexError：索引超出范围
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List = [2]
>>> List[3]
Traceback (most recent call last):
  File "<pyshell#18>", line 1, in <module>
    List[3]
IndexError: list index out of range
  • KeyError：字典关键字不存在
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Dic = {'1':'yes', '2':'no'}
>>> Dic['3']
Traceback (most recent call last):
  File "<pyshell#20>", line 1, in <module>
    Dic['3']
KeyError: '3'
  • IOError：输入输出错误
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>>> f = open('abc')
IOError: [Errno 2] No such file or directory: 'abc'
  • AttributeError：访问未知对象属性
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>>> class Worker:
 def Work():
  print("I am working")

>>> w = Worker()
>>> w.a
Traceback (most recent call last):
  File "<pyshell#51>", line 1, in <module>
    w.a
AttributeError: 'Worker' object has no attribute 'a'
  • ValueError：数值错误
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>>> int('d')
Traceback (most recent call last):
  File "<pyshell#54>", line 1, in <module>
    int('d')
ValueError: invalid literal for int() with base 10: 'd'
  • TypeError：类型错误
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>>> iStr = '22'
>>> iVal = 22
>>> obj = iStr + iVal;
Traceback (most recent call last):
  File "<pyshell#68>", line 1, in <module>
    obj = iStr + iVal;
TypeError: Can't convert 'int' object to str implicitly
  • AssertionError：断言错误
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>>> assert 1 != 1
Traceback (most recent call last):
  File "<pyshell#70>", line 1, in <module>
    assert 1 != 1
AssertionError
  • MemoryError:内存耗尽异常
  • NotImplementedError：方法没实现引起的异常
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class Base(object):
    def __init__(self):
        pass

    def action(self):
        #抛出异常，说明该接口方法未实现
        raise NotImplementedError
  • LookupError：键、值不存在引发的异常

LookupError异常是IndexError、KeyError的基类， 如果你不确定数据类型是字典还是列表时，可以用LookupError捕获此异常

  • StandardError: 标准异常

除StopIteration, GeneratorExit, KeyboardInterrupt 和SystemExit外，其他异常都是StandarError的子类。