day10-python基础之字符串

 1 #!/usr/bin/env python
 2 # -*- coding:utf8 -*-
 3 #int
 4 a = "123"
 5 print(type(a), a)
 6 
 7 b = int(a)
 8 print(type(b), b)
 9 
10 num = "0011"
11 v = int(num, base=16)
12 print(v)

1 #!/usr/bin/env python
2 # -*- coding:utf8 -*-
3 #int
4 age = 5
5 r = age.bit_length()
6 print(r)

1 #!/usr/bin/env python
2 # -*- coding:utf8 -*-
3 #str
4 # 首字母大写 capitalize()
5 test = "aLex"
6 v = test.capitalize()
7 print(v)

1 #!/usr/bin/env python
2 # -*- coding:utf8 -*-
3 #str
4 # 所有变小写 casefold()  lower()
5 test = "ShiQIanYu"
6 v1 = test.casefold()
7 print(v1)
8 v2 = test.lower()
9 print(v2)

1 #!/usr/bin/env python
2 # -*- coding:utf8 -*-
3 #str
4 test = 'sqy'
5 v = test.center(20,"*")
6 print(v)

 1 #!/usr/bin/env python
 2 # -*- coding:utf8 -*-
 3 #str
 4 test = "aLexalexr"
 5 v = test.count('ex')
 6 print(v)
 7 
 8 test = "aLexalexr"
 9 v = test.count('ex',6,8)
10 print(v)

 1 #!/usr/bin/env python
 2 # -*- coding:utf8 -*-
 3 #str
 4 # 以什么什么结尾
 5 # 以什么什么开始
 6 test = "alex"
 7 v = test.endswith('ex')
 8 print(v)
 9 v = test.startswith('alex')
10 print(v)

1 #!/usr/bin/env python
2 # -*- coding:utf8 -*-
3 #str
4 # 从开始往后找，找到第一个之后，获取其未知
5 # > 或 >=
6 test = "alexalex"
7 # 未找到 -1
8 v = test.find('ex')
9 print(v)

1 #!/usr/bin/env python
2 # -*- coding:utf8 -*-
3 #str
4 test = "alexalex"
5 v = test.index('8')
6 print(v)

 1 # -*- coding:utf8 -*-
 2 #str
 3 test = 'i am {name}, age {a}'
 4 print(test)
 5 v = test.format(name='alex',a=19)
 6 print(v)
 7 
 8 test = 'i am {0}, age {1}'
 9 print(test)
10 v = test.format('alex',19)
11 print(v)

1 #!/usr/bin/env python
2 # -*- coding:utf8 -*-
3 #str
4 # 格式化，传入的值 {"name": 'alex', "a": 19}
5 test = 'i am {name}, age {a}'
6 v1 = test.format(name='df',a=10)
7 print(v1)
8 v2 = test.format_map({"name": 'alex', "a": 19})
9 print(v2)

1 #!/usr/bin/env python
2 # -*- coding:utf8 -*-
3 #str
4 # 字符串中是否只包含 字母和数字 汉字
5 test = "as123对的？"
6 v = test.isalnum()
7 print(v)