Python学习心得第二周-02

print(‘*****egon*****‘.strip(‘*‘))
print(‘*****egon*****‘.lstrip(‘*‘))
print(‘*****egon*****‘.rstrip(‘*‘))

print(‘aaAbCCC‘.lower())
print(‘aaAbCCC‘.upper())

print(‘alex is sb‘.startswith(‘alex‘))
print(‘alex is sb‘.endswith(‘sb‘))

print(‘my name is %s my age is %s‘ %(18,‘egon‘))
print(‘my name is {name} my age is {age}‘.format(age=18,name=‘egon‘))

print(‘my name is {} my age is {}‘.format(18,‘egon‘))
print(‘my name is {0}{0}{0} my age is {1}‘.format(18,‘egon‘))

cmd=‘get|a.txt|3333‘

print(cmd.split(‘|‘,1))
print(cmd.rsplit(‘|‘,1))

info=‘root:x:0:/root:bin/root‘
res=info.split(‘:‘)#先去除分隔符，以列表显示
print(res,type(res))
info1=‘:‘.join(res)#将：再次插入到列表数据中
print(info1)

msg=‘my name is alex,alex say hello‘
print(msg.replace(‘alex‘,‘SB‘,1))
print(msg)

print(‘10123‘.isdigit())

#--------------------------------------------------

age_of_db=50
age_of_inp=input(‘>>>: ‘).strip() #age_of_inp=‘sadfsadfasdf‘
if age_of_inp.isdigit():
    age_of_inp=int(age_of_inp)
    if age_of_inp > age_of_db:
        print(‘too big‘)
    elif age_of_inp < age_of_db:
        print(‘too small‘)
    else:
        print(‘you got it‘)
else:
    print(‘必须输入数字啊傻叉‘)

#find,rfind,index,rindex,count
name=‘egon say hello‘
print(name.find(‘o‘,1,3)) #顾头不顾尾,找不到则返回-1不会报错,找到了则显示索引
# print(name.index(‘e‘,2,4)) #同上,但是找不到会报错
print(name.count(‘e‘,1,3)) #顾头不顾尾,如果不指定范围则查找所有

#center,ljust,rjust,zfill
name=‘egon‘
print(name.center(30,‘-‘))
print(name.ljust(30,‘*‘))
print(name.rjust(30,‘*‘))
print(name.zfill(50)) #用0填充

#expandtabs
name=‘egon\thello‘
print(name)
print(name.expandtabs(1))

#captalize,swapcase,title
print(name.capitalize()) #首字母大写
print(name.swapcase()) #大小写翻转
msg=‘egon say hi‘
print(msg.title()) #每个单词的首字母大写

#is数字系列
#在python3中
num1=b‘4‘ #bytes
num2=u‘4‘ #unicode,python3中无需加u就是unicode
num3=‘四‘ #中文数字
num4=‘Ⅳ‘ #罗马数字

#isdigt:bytes,unicode
print(num1.isdigit()) #True
print(num2.isdigit()) #True
print(num3.isdigit()) #False
print(num4.isdigit()) #False

#isdecimal:uncicode
#bytes类型无isdecimal方法
print(num2.isdecimal()) #True
print(num3.isdecimal()) #False
print(num4.isdecimal()) #False

#isnumberic:unicode,中文数字,罗马数字
#bytes类型无isnumberic方法
print(num2.isnumeric()) #True
print(num3.isnumeric()) #True
print(num4.isnumeric()) #True

#三者不能判断浮点数
num5=‘4.3‘
print(num5.isdigit())
print(num5.isdecimal())
print(num5.isnumeric())
‘‘‘
总结:
    最常用的是isdigit,可以判断bytes和unicode类型,这也是最常见的数字应用场景
    如果要判断中文数字或罗马数字,则需要用到isnumeric
‘‘‘

#is其他
print(‘===>‘)
name=‘egon123‘
print(name.isalnum()) #字符串由字母或数字组成
print(name.isalpha()) #字符串只由字母组成

print(name.isidentifier())
print(name.islower())
print(name.isupper())
print(name.isspace())
print(name.istitle())