简体中文(ZH-CN) English(EN) 繁体中文(ZH-TW)
Home > Backend Development > Python Tutorial > body text

Python中请使用isinstance()判断变量类型

WBOY
Release： 2016-06-16 08:42:31
Original
1724 people have browsed it

一、isinstance()

在Python中可以使用type()与isinstance()这两个函数判断对象类型，而isinstance()函数的使用上比type更加方便。

复制代码 代码如下:

# coding=utf-8
 
a = 10
 
def b():
    pass
 
print isinstance(a,(int,str))
print isinstance(a,(float,str))
print isinstance(b,(str,int))
 
class c:
    pass
 
obj = c()
 
print isinstance(obj,(c,int))

执行结果：
复制代码 代码如下:

True
False
False
True

二、isinstance 和 type的区别

isinstance 和 type的区别在于：

复制代码 代码如下:

class A:
    pass

class B(A):
    pass

isinstance(A(), A)  # returns True
type(A()) == A      # returns True
isinstance(B(), A)    # returns True
type(B()) == A        # returns False


区别就是 对于subclass之类的 type就不行了，所以,强烈建议不要使用type判断对象类型。
Related labels：
isinstance() python Determine variable type
source：php.cn
Previous article：python常用web框架简单性能测试结果分享(包含django、flask、bottle、tornado) Next article：Python中变量交换的例子
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Latest Articles by Author
Latest Issues
How to run python script from HTML in google chrome? I'm building a chrome extension and I want to run a python script from my PC by clicking a...
From 2023-11-02 23:34:24
0
1
400
Why do some mysql connections select old data of mysql database after delete+insert? I have a problem with sessions in my python/wsgiweb application. Each thread in the 2 wsgi...
From 2023-10-30 12:37:20
0
2
229
Using variables to execute SQL statements in Python I have the following Python code: cursor.execute("INSERTINTOtableVALUESvar1,var2,var3...
From 2023-10-12 15:06:00
0
2
258
Understanding the ternary operator in Python [duplicate] I'm currently transitioning from JavaScript to Python, and I'm wondering if Python has a t...
From 2023-09-21 18:46:04
0
1
377
How to match strings with appended parts using Python, but not match them if their appended parts are different How to match strings with appended parts, but not match them if they have different append...
From 2023-09-20 19:02:23
0
1
260
Related Topics
More>
Popular Recommendations
Popular Tutorials
More>
Related Tutorials
Popular Recommendations
Latest courses
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template
About us Disclaimer Sitemap
php.cn：Public welfare online PHP training，Help PHP learners grow quickly！