python开发之str.format()用法实例分析_Python

python开发之str.format()用法实例分析

2020-08-13 10:53Hongten Python

这篇文章主要介绍了python开发之str.format()用法,结合实例形式较为详细的分析了str.format()函数的功能,使用方法与相关注意事项,代码包含详尽的注释说明,需要的朋友可以参考下

本文实例分析了python开发之str.format()用法。分享给大家供大家参考，具体如下：

格式化一个字符串的输出结果，我们在很多地方都可以看到，如：c/c++中都有见过

下面看看python中的字符串格式函数str.format():

				?

									#使用str.format()函数

									#使用'{}'占位符

									print('I\'m {},{}'.format('Hongten','Welcome to my space!'))

									print('#' * 40)

									#也可以使用'{0}','{1}'形式的占位符

									print('{0},I\'m {1},my E-mail is {2}'.format('Hello','Hongten','hongtenzone@foxmail.com'))

									#可以改变占位符的位置

									print('{1},I\'m {0},my E-mail is {2}'.format('Hongten','Hello','hongtenzone@foxmail.com'))

									print('#' * 40)

									#使用'{name}'形式的占位符

									print('Hi,{name},{message}'.format(name = 'Tom',message = 'How old are you?'))

									print('#' * 40)

									#混合使用'{0}','{name}'形式

									print('{0},I\'m {1},{message}'.format('Hello','Hongten',message = 'This is a test message!'))

									print('#' * 40)

									#下面进行格式控制

									import math

									print('The value of PI is approximately {}.'.format(math.pi))

									print('The value of PI is approximately {!r}.'.format(math.pi))

									print('The value of PI is approximately {0:.3f}.'.format(math.pi))

									table = {'Sjoerd': 4127, 'Jack': 4098, 'Dcab': 7678}

									for name, phone in table.items():

									  print('{0:10} ==> {1:10d}'.format(name, phone))

									table = {'Sjoerd': 4127, 'Jack': 4098, 'Dcab': 8637678}

									print('Jack: {0[Jack]:d}; Sjoerd: {0[Sjoerd]:d}; ''Dcab: {0[Dcab]:d}'.format(table))

运行效果：

				?

									Python 3.3.2 (v3.3.2:d047928ae3f6, May 16 2013, 00:03:43) [MSC v.1600 32 bit (Intel)] on win32

									Type "copyright", "credits" or "license()" for more information.

									>>> ================================ RESTART ================================

									>>> 

									I'm Hongten,Welcome to my space!

									########################################

									Hello,I'm Hongten,my E-mail is hongtenzone@foxmail.com

									Hello,I'm Hongten,my E-mail is hongtenzone@foxmail.com

									########################################

									Hi,Tom,How old are you?

									########################################

									Hello,I'm Hongten,This is a test message!

									########################################

									The value of PI is approximately 3.141592653589793.

									The value of PI is approximately 3.141592653589793.

									The value of PI is approximately 3.142.

									Jack    ==>    4098

									Sjoerd   ==>    4127

									Dcab    ==>    7678

									Jack: 4098; Sjoerd: 4127; Dcab: 8637678

									>>>