英文文档：

复制代码 代码如下:oct ( x )
Convert an integer number to an octal string. The result is a valid Python expression. If x is not a Pythonobject, it has to define anmethod that returns an integer.

说明：

1. 函数功能将一个整数转换成8进制字符串。如果传入浮点数或者字符串均会报错。

>>> a = oct(10)>>> a'0o12'>>> type(a) # 返回结果类型是字符串<class 'str'>>>> oct(10.0) # 浮点数不能转换成8进制Traceback (most recent call last): File "<pyshell#3>", line 1, in <module> oct(10.0)TypeError: 'float' object cannot be interpreted as an integer>>> oct('10') # 字符串不能转换成8进制Traceback (most recent call last): File "<pyshell#4>", line 1, in <module> oct('10')TypeError: 'str' object cannot be interpreted as an integer

2. 如果传入参数不是整数，则其必须是一个定义了__index__并返回整数函数的类的实例对象。

# 未定义__index__函数，不能转换>>> class Student: def __init__(self,name,age): self.name = name self.age = age >>> a = Student('Kim',10)>>> oct(a)Traceback (most recent call last): File "<pyshell#12>", line 1, in <module> oct(a)TypeError: 'Student' object cannot be interpreted as an integer# 定义了__index__函数，但是返回值不是int类型，不能转换>>> class Student: def __init__(self,name,age): self.name = name self.age = age def __index__(self): return self.name>>> a = Student('Kim',10)>>> oct(a)Traceback (most recent call last): File "<pyshell#18>", line 1, in <module> oct(a)TypeError: __index__ returned non-int (type str)# 定义了__index__函数，而且返回值是int类型，能转换>>> class Student: def __init__(self,name,age): self.name = name self.age = age def __index__(self): return self.age>>> a = Student('Kim',10)>>> oct(a)'0o12'