Python Development Basics-String Type Tutorial (String method)-1

s = ' Hello world! '

Print (S.capitalize ()) #第一个字母大写, remaining lowercase
# Output: Hello world!
Print (S.swapcase ()) #大写变小写, lowercase to uppercase
#输出: HELLO world!
Print (S.casefold ()) #全变小写
#输出: Hello world!
Print (S.center, '-') #S字符字符串在总50宽度的居中位置, with "-" padding on both sides
#输出:-------------------Hello World!-------------------
Print (S.count (' l ')) #统计字符串中有多少个 ' l '
#输出: 3
Print (S.count (' l ', 0,5)) #统计字符串中从第一个字母到第5个字母, how many ' l '
#输出: 2
Print (S.endswith (' d ')) #判断字符串是否已 ' d ' end
#输出: FALSE
Print (S.expandtabs ()) #定义TAB键字符的宽度
Print (S.find (' O ')) #查找一个字符或字符串的位置 (index), not found, returned-1
#输出:, 4
Print (S.find (' dfdf '))
#输出:-1
S3 = ' My name si {0},i am {1} years old '
Print (S3.format (' Zhang San ', +)) #格式化输出
#输出: My name si Zhang San,i am years old
S3 = ' My name si {name},i am {age} years old ' #格式化支持定义占位符
Print (S3.format (name= ' Zhangsan ', age=23)) #给占位符赋值

Python Development Basics-String Type Tutorial (String method)-1