python 基础之字符串方法

字符串

print('chenxi'*8)

　　测试

D:\python\python.exe D:/untitled/dir/for.py
chenxichenxichenxichenxichenxichenxichenxichenxi

Process finished with exit code 0

　　字符串切片打印处理

print('chenxi'[2:])

　　测试

D:\python\python.exe D:/untitled/dir/for.py
enxi

　　判断字符串里有没有包含对应得字符

print('x'in 'chenxi')
print('f'in 'chenxi')

　　测试

True
False

　　字符串拼接，不建议使用这种方法

a='cx'
b='zrd'
c=a+b
print(c)

　　测试

D:\python\python.exe D:/untitled/dir/for.py
cxzrd

Process finished with exit code 0

　　字符串拼接

a='cx'
b='zrd'
c=''.join([a,b])
print(c)

　　测试

D:\python\python.exe D:/untitled/dir/for.py
cxzrd

Process finished with exit code 0

　　字符串拼接

a='cx'
b='zrd'
bb='haha'
c='-----'.join([a,b,bb])
print(c)

　　测试

D:\python\python.exe D:/untitled/dir/for.py
cx-----zrd-----haha

　　字符串之统计关键字个数

dis = 'hebei tianjing guanzhou'
print(dis.count('i'))

　　测试

D:\python\python.exe D:/untitled/dir/for.py
3

　　字符串之修改首字母为大写

dis = 'hebei tianjing guanzhou'
print(dis.capitalize())

　　测试

D:\python\python.exe D:/untitled/dir/for.py
Hebei tianjing guanzhou

　　一共打印50字符，不够用指定字符去补，原先字符串内容居中

dis = 'hebei tianjing guanzhou'
print(dis.center(50,'#'))

　　测试

D:\python\python.exe D:/untitled/dir/for.py
#############hebei tianjing guanzhou##############

Process finished with exit code 0

　　判断字符串是不是以什么结尾的

dis = 'hebei tianjing guanzhou'
print(dis.endswith('u'))
print(dis.endswith('i'))

　　测试

D:\python\python.exe D:/untitled/dir/for.py
True
False

Process finished with exit code 0

　　判断字符串是不是以什么开头的

dis = 'hebei tianjing guanzhou'
print(dis.startswith('he'))

　　测试

D:\python\python.exe D:/untitled/dir/for.py
True

Process finished with exit code 0

　　修改字符串里tab的默认空格数量\t 表示tab键

dis = 'he\tbei tianjing guanzhou'
print(dis.expandtabs(tabsize=10))

　　测试

D:\python\python.exe D:/untitled/dir/for.py
he        bei tianjing guanzhou

Process finished with exit code 0

　　找到字符串里第一个元素定返回索引值

dis = 'hebei tianjing guanzhou'
print(dis.find('a'))

　　测试

D:\python\python.exe D:/untitled/dir/for.py
8

　　将字符串变量赋值打印

dis = 'hebei tianjing guanzhou {name}'
print(dis.format(name='zrd'))

　　测试

D:\python\python.exe D:/untitled/dir/for.py
hebei tianjing guanzhou zrd

Process finished with exit code 0

　　以字典方式批量给字符串赋值

dis = 'hebei tianjing guanzhou {name} ll {age}'
print(dis.format_map({'name':'zrd','age':22}))

　　测试

D:\python\python.exe D:/untitled/dir/for.py
hebei tianjing guanzhou zrd ll 22

Process finished with exit code 0

　　查字符串里关键字并返回索引值，字符串里没有关键字报错

dis = 'hebei tianjing guanzhou {name} ll {age}'
print(dis.index('i'))
print(dis.index('d'))

　测试

D:\python\python.exe D:/untitled/dir/for.py
Traceback (most recent call last):
  File "D:/untitled/dir/for.py", line 170, in <module>
    print(dis.index('d'))
ValueError: substring not found
4

　　判断字符串是否包含特殊字符

print('test564'.isalnum() )
print('tygc*'.isalnum())
print('reswd'.isalnum())
print('7890'.isalnum())
print('宋氏家族'.isalnum())

　　测试

D:\python\python.exe D:/untitled/dir/for.py
True
False
True
True
True

　　判断字符串像不像十进制的数字

print("3455".isdecimal())
print("程序".isdecimal())
print("AF09".isdecimal())
print("hevb".isdecimal())

　　测试

D:\python\python.exe D:/untitled/dir/for.py
True
False
False
False

　　判断字符串是否包含一个非法字符

print("dtfghvh".isidentifier())
print("1233tyghgvh".isidentifier())  #非法字符

　　测试

D:\python\python.exe D:/untitled/dir/for.py
True
False

　　判断字符是不是空格

print(' '.isspace())

　　测试

D:\python\python.exe D:/untitled/dir/for.py
True

Process finished with exit code 0

　　判断字符串是不是标题格式

print('My Ch'.istitle())
print('My ch'.istitle())

　　测试

True
False

　　字符串里所有大写改成小写

print('My Ch'.lower())

　　测试

D:\python\python.exe D:/untitled/dir/for.py
my ch

Process finished with exit code 0

　　字符串所有小写该大写

print('My Ch'.upper())

　　测试

D:\python\python.exe D:/untitled/dir/for.py
MY CH

Process finished with exit code 0

　　字符串中大小写翻转

print('My Ch'.swapcase())

　　测试

D:\python\python.exe D:/untitled/dir/for.py
mY cH

Process finished with exit code 0

　　在字符串后面以特定字符补够特定数量

print('My Ch'.ljust(50，'*'))

　　测试

D:\python\python.exe D:/untitled/dir/for.py
My Ch*********************************************

Process finished with exit code 0

　　在字符串前面以特定字符补够特定数量

print('My Ch'.rjust(50,'*'))

　　测试

D:\python\python.exe D:/untitled/dir/for.py
*********************************************My Ch

Process finished with exit code 0

　　将字符串前后空格去掉

print('       My Ch'.strip())

　　测试

D:\python\python.exe D:/untitled/dir/for.py
My Ch

Process finished with exit code 0

　　字符串内容替换

print('chenxi ffff'.replace('ffff','zrd'))

　　测试

D:\python\python.exe D:/untitled/dir/for.py
chenxi zrd

Process finished with exit code 0

　　字符串内容替换的次数控制

print('chenxi ffff'.replace('ffff','zrd'))
print('chenxi ffff  tygdf'.replace('ff','zrd'))
print('chenxi ffff  tygdf'.replace('ffff','zrd',1))

　　测试

D:\python\python.exe D:/untitled/dir/for.py
chenxi zrd
chenxi zrdzrd  tygdf
chenxi zrd  tygdf

Process finished with exit code 0

　　查字符串最后一个关键字在第几个索引

print('chenxi cx xlc'.rfind('x'))

　测试

D:\python\python.exe D:/untitled/dir/for.py
10

Process finished with exit code 0

　　将字符串以空格为分隔符，分成列表

print('chenxi cx xlc'.split(' '))

　　测试

D:\python\python.exe D:/untitled/dir/for.py
['chenxi', 'cx', 'xlc']

Process finished with exit code 0