import types
type(x) is types.IntType # 判断是否int 类型 type(x) is types.StringType #是否string类型 .........--------------------------------------------------------
超级恶心的模式，不用记住types.StringType
import types
type(x) == types(1) # 判断是否int 类型 type(x) == type('a') #是否string类型------------------------------------------------------
使用内嵌函数：
isinstance ( object, classinfo )
Return true if the object argument is an instance of the classinfo argument, or of a (direct or indirect) subclass thereof. Also return true if classinfo is a type object and object is an object of that type. If object is not a class instance or an object of the given type, the function always returns false. If classinfo is neither a class object nor a type object, it may be a tuple of class or type objects, or may recursively contain other such tuples (other sequence types are not accepted). If classinfo is not a class, type, or tuple of classes, types, and such tuples, a TypeError exception is raised. Changed in version 2.2: Support for a tuple of type information was added.
Python可以得到一个对象的类型 ，利用type函数：>>>lst = [1, 2, 3]
>>>type(lst)<type 'list'> 不仅如此，还可以利用isinstance函数，来判断一个对象是否是一个已知的类型。isinstance说明如下:
isinstance(object, class-or-type-or-tuple) -> bool
Return whether an object is an instance of a class or of a subclass thereof. With a type as second argument, return whether that is the object's type. The form using a tuple, isinstance(x, (A, B, ...)), is a shortcut for isinstance(x, A) or isinstance(x, B) or ... (etc.).其第一个参数为对象，第二个为类型名或类型名的一个列表。其返回值为布尔型。若对象的类型与参数二的类型相同则返回True。若参数二为一个元组，则若对象类型与元组中类型名之一相同即返回True。
>>>isinstance(lst, list)
Trueisinstance(lst, (int, str, list))True>>>isinstance(lst, (int, str, list))
True
python数据类型判断type与isinstance的区别
在项目中，我们会在每个接口验证客户端传过来的参数类型，如果验证不通过，返回给客户端“参数错误”错误码。
这样做不但便于调试，而且增加健壮性。因为客户端是可以作弊的，不要轻易相信客户端传过来的参数。
验证类型用type，非常好用，比如
>>type('foo') == str
True
>>type(2.3) in (int,float)
True
既然有了type()来判断类型，为什么还有isinstance()呢？
一个明显的区别是在判断子类。
type()不会认为子类是一种父类类型。
isinstance()会认为子类是一种父类类型。
千言不如一码。
class Foo( object ): pass class Bar(Foo): pass print type (Foo()) = = Foo print type (Bar()) = = Foo print isinstance (Bar(),Foo) class Foo( object ): pass class Bar(Foo): pass print type (Foo()) = = Foo print type (Bar()) = = Foo print isinstance (Bar(),Foo) 输出 True False True |
需要注意的是，旧式类跟新式类的type()结果是不一样的。旧式类都是<type 'instance'>。
class A: pass class B: pass class C( object ): pass print 'old style class' , type (A()) print 'old style class' , type (B()) print 'new style class' , type (C()) print type (A()) = = type (B()) class A: pass class B: pass class C( object ): pass print 'old style class' , type (A()) print 'old style class' , type (B()) print 'new style class' , type (C()) print type (A()) = = type (B()) 输出 old style class < type 'instance' > old style class < type 'instance' > new class < class '__main__.C' > True |
不存在说isinstance比type更好。只有哪个更适合需求。