Python练习9---string

字符串是 Python 中最常用的数据类型,可以使用引号(‘或”)来创建字符串。具体相关操作可以去网页上学习
英文：https://www.tutorialspoint.com/python/python_strings.htm
中文：http://www.runoob.com/python/python-strings.html

1、字符串的定义和获取：使用下标

# Hello World program in Python# -*- coding: utf8 -*-import os,syssay="hello!Morning"i=0#字符串操作while i < len(say):    print(i, "  =  ",say[i])    i=i+1

运行结果

2、使用切片方式

#!python# -*- coding: utf8 -*-import os,syssay="hello!Morning"print("len",len(say))print(say[0:5])print(say[5:])print(say[5:13])print(say[0:-7])print(say[:-7])

运行结果

3、字符串连接：+

#!python# -*- coding: utf8 -*-import os,syssay="hello!"say=say+"Morning"print("len",len(say))print(say[0:5])print(say[5:])print(say[5:13])print(say[0:-7])print(say[:-7])

运行结果

4、字符串长度获取：len

#!python# -*- coding:utf8 -*-import os,syssay="hello!"say1=say+"Morning"print("len",say1,len(say1))say2="%s%s"%(say,"Morning")print("len",say2,len(say2))say3="len %s %d"%(say2,len(say2))print(say3)

运行结果

5、字符串替换：replace
string.replace(str1, str2, num=string.count(str1))
把 string 中的 str1 替换成 str2,如果 num 指定，则替换不超过 num 次.

#!python# -*- coding:utf8 -*-import os,syssay="hello!"say1=say+"Morning"print("len",say1,len(say1))say1=say1.replace("hello","Hello ")print("len",say1,len(say1))b=say1.find("Morning")c=say1[b:]print("len",c,len(c))

运行结果