字符串类型

定义方式：' '," ",''' '''.

按索引取值（正向取+反向取）：只能取

result = 'hello,world'
print(result[2])
print(result[-1])

2.切片（顾头不顾尾）

result = 'hello,world'
print(result[6:])
print(result[:2])
print(result[0:3])
print(result[-3: -1])
print(result[0:6:2])

3.长度

result = 'hello,world'
print(len(result))
l = [1,2,3,'a','b', [1,2,3]]
print(len(l))
t = (1,2,3,4)
print(len(t))
result = {
    'a': 1,
    'b': 2,
    'c': 3
}
print(len(result))

4.成员运算（in，not in）

result = 'hello,world'
result = '1888这个班好牛X！'
if 'X牛' in result:
    print('ok')
else:
    print('不OK')
if '牛X' not in result:
    print('ok')
else:
    print('不OK')

5.移除空白（strip，lstrip，rstrip）

result = '------LINUX------'
print(result.rstrip('-')) #strip()不加参数，默认是空格

6.切分split，rsplit（把一个字符串变成列表）

result = '192.168.1.250'
print(result.split('.'))
result = '192 168 1 250'
print(result.split()) #split()默认按空格分割,从左往右分割
print(result.rsplit('.', 1)) #rsplit()从右往左分割
print(result.split('.', 1))

7.lower，upper，title（小写，大写，抬头）

content = 'linux'
result = content.upper()
print(result.lower())

name = 'helloworld'
print(name.title())

8.startswith endswith（判断字符串开头和结尾）

name = 'hello world'
print(name.startswith('o'))
print(name.endswith('s'))

9.format（格式化）

result = 'my name is {} my age is {}'.format('oyy', 18)
print(result)

result = 'my name is {name} my age is {age}'.format(age = 18, name='oyy')
print(result)

10.replace（替换）

result = 'my name is oyy my age is 18'.replace('my', 'your', 1)
print(result)

11.了解（str.find, rfind, index, rindex, count）

# result = 'mynameisfengzimyageis18'.index('y')
# result = 'mynameisfengzimyageis18'.find('fengzi')
# result = 'mynameisfengzimyageis18'.count('my')
# print(result)