python入门8 （字符串）

1.字符串的创建和驻留机制

 

a='python'
b="python"
c='''python'''
print(a,id(a))
print(b,id(b))
print(c,id(c))

2.字符串的查找

 

'''字符串的查找操作'''
s='hello,hello'
print(s.index('lo'))
print(s.find('lo'))
print(s.rindex('lo'))
print(s.rfind('lo'))

#print(s.index('k')) #ValueError: substring not found
#print(s.rindex('k')) #ValueError: substring not found
print(s.find('k')) #-1
print(s.rfind('k')) #-1

3.字符串比较大小写

'''字符串中大小写转换的方法'''
s = 'hello,python'
a = s.upper()
print(a, id(a))
print(s, id(s))
b = s.lower()
print(b, id(b))
print(s, id(s))
print(b == s)
print(b is s)

c = 'hello,Python'
print(c.swapcase())
print(c.capitalize())
print(c.title())