python3中str的使用

前言

在程序中，需要对str(字符串)进行处理

使用

字符串与数字相乘

>>> a = "xyz"
>>> a * 2
'xyzxyz'
           

三引号(""""""/’’’’’’)的使用

示例1

>>> a = """c
... java
... python"""
>>> print(a)
c
java
python
           

示例2

>>> a = '''c
... java
... python'''
>>> print(a)
c
java
python
           

示例3

>>> a = """I don't know"""
>>> print(a)
I don't know
           

格式化字符串

方法1

''含有%s的字符串" % “要插入的字符串”

• 示例

>>> a = "uvw%sxyz" % "nature"
>>> print(a)
uvwnaturexyz
           

方法2

“含有{}的字符串”.format(“要插入的字符串”)

• 示例

>>> a = "uvw{}xyz".format("nature")
>>> print(a)
uvwnaturexyz
           

切片

>>> a = 'uvwnaturexyz'
>>> a[:3]
'uvw'
>>> a[-3:]
'xyz'
           

去掉字符串的空格符、制表符(\t)、换行符(\n、\r\n)等

方法

str.split()

示例

> python
Python 3.8.2 (tags/v3.8.2:7b3ab59, Feb 25 2020, 23:03:10) [MSC v.1916 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> confirm = "version\t8.0.23\r\n"
>>> confirm.split()
['version', '8.0.23']

           

去掉字符串的"

方法

str.replace(’"’, ‘’)

示例

>>> confirm = '"nature'
>>> print(confirm.replace('\"', ''))
nature