python中的isprintable函数_函数解析——python学习第三次总
结
.str字符串类型(⼆)
1. isalpha 判断⽬标字符串中是否只含字母
表达式 str.isalpha() ==> bool
⽰例：我哭得好无力
1 a = 'alex'
2 v =a.isalpha()黑茶属于什么茶
3 print(v)
# 输出
# True
源码：
1 def isalpha(lf, *args, **kwargs): #real signature unknown
2 """
3 Return True if the string is an alphabetic string, Fal otherwi.4
5 A string is alphabetic if all characters in the string are alphabetic and there
6 is at least one character in the string.
7 """
源码
2. isdecimal
isdigit 都是⽤来判断⽬标字符串是否是数字，上⾯这个是在⼗进制范围内，下⾯这个不光能判断纯⽂本，还能判断复杂符号。
表达式 str.isdecimal() ==> bool
str.isdigit() ==> bool
⽰例：
1 a = '②'
2 b =a.isdecimal()
3 c =a.isdigit()
4 print(b,c)
# 输出
# fal true
源码：
1 def isdecimal(lf, *args, **kwargs): #real signature unknown
2 """
3 Return True if the string is a decimal string, Fal otherwi.4
5 A string is a decimal string if all characters in the string are decimal and
6 there is at least one character in the string.
7 """ isdecimal
1 def isdigit(lf, *args, **kwargs): #real signature unknown
2 """
3 Return True if the string is a digit string, Fal otherwi.4
申请调查令申请书
5 A string is a digit string if all characters in the string are digits and there
6 is at least one character in the string.
7 """ isdigit
3. isidentifier 判断⽬标字符串是否只含数字、字母、下划线，即判断出是否是属于变量名称。
表达式 str.isidentifier() ==> bool
⽰例：
1 print('def_class123'.isidentifier())
# 输出
# true
源码
1 def isidentifier(lf, *args, **kwargs): #real signature unknown
2 """
3 Return True if the string is a valid Python identifier, Fal otherwi.4
5 U keyword.iskeyword() to test for rerved identifiers such as "def" and
6 "class".
7 """
源码
4. isspace ⽬标字符串中是否只含有空格
表达式 str.isspace() ==> bool
⽰例：
1 print(' '.isspace())
# 输出
酒字书法
# true
水的三态
源码：
1 def isspace(lf, *args, **kwargs): #real signature unknown
2 """
3 Return True if the string is a whitespace string, Fal otherwi.4
5 A string is whitespace if all characters in the string are whitespace and there
6 is at least one character in the string.
7 """源码
5. islower 判断⽬标字符串中的所有英⽂字母是否是⼩写
表达式 str.islower() ==> bool
⽰例：
1 print('adsf_②123贰⼆'.islower())
# 输出
# TRUE
源码：
1 def islower(lf, *args, **kwargs): #real signature unknown
2 """
3 Return True if the string is a lowerca string, Fal otherwi.4
5 A string is lowerca if all cad characters in the string are lowerca and
6 there is at least one cad character in the string.
7 """
源码
6. isnumeric 判断⽬标字符串是否只含数字(含字符数字)
表达式 str.isnumeric() ==> bool
⽰例：
1 print('②Ⅱ123贰⼆'.isnumeric())
# 输出
# true
源码：
1 def isnumeric(lf, *args, **kwargs): #real signature unknown
2 """
3 Return True if the string is a numeric string, Fal otherwi.4
5 A string is numeric if all characters in the string are numeric and there is at
6 least one character in the string.
7 """
源码
7. isprintable 判断字符串是否可打印(是否可以打印决定于⾥⾯是否有不可显⽰字符。换⾔之⾥⾯不可复⽤函数，需先输出结果)
什么叫散文
表达式 str.isprintable() ==> bool
⽰例：
1 print('er⼆贰②——'.isprintable())
# 输出
# TRUE
源码：
1 def isprintable(lf, *args, **kwargs): #real signature unknown
2 """
3 Return True if the string is printable, Fal otherwi.4
5 A string is printable if all of its characters are considered printable in
6 repr() or if it is empty.
7 """
源码
8. istitle ⽬标字符串中是否是标题(即满⾜每个单词⾸字母⼤写)
表达式 str.istitle() ==> bool
⽰例：
1 print('Return True if the string is a valid Python identifier'.istitle())
# 输出
# fal
源码：
1 def istitle(lf, *args, **kwargs): #real signature unknown
2 """
3 Return True if the string is a title-cad string, Fal otherwi.4
5 In a title-cad string, upper- and title-ca characters may only
6 follow uncad characters and lowerca characters only cad ones.
7 """
源码
9. title 将⽬标字符串转换为标题格式(即转换为每个单词⾸字母⼤写)
表达式： str.title() ==> str
⽰例：
1 print('Return True if the string is a valid Python identifier'.title())
# 输出
# Return True If The String Is A Valid Python Identifier
源码：
1 def title(lf, *args, **kwargs): #real signature unknown
2 """
3 Return a version of the string where each word is titlecad.4
5 More specifically, words start with uppercad characters and all remaining
6 cad characters have lower ca.
7 """
源码
10. join 将设置字符插⼊⽬标字符串中每个字符中间
表达式 str.join(iterable) ==> str
⽰例：
1 print('-'.join('你是风⼉我是沙'))
# 输出
# 你-是-风-⼉-我-是-沙
源码：
1 def join(lf, ab=None, pq=None, rs=None): #real signature unknown; restored from __doc__
2 """
3 Concatenate any number of strings.4
5 The string who method is called is inrted in between each given string.
6 The result is returned as a new string.
7
8 Example: '.'.join(['ab', 'pq', 'rs']) -> 'ab.pq.rs'
9 """
蒙古包图片源码
小学200字作文11. ljust 原有字符串在左⽅，右⽅添加指定字符
表达式 str.ljust(width,fillchar) ==> str
width 总格式化宽度
fillchar 插⼊字符
⽰例：
1 print('alex'.ljust(20,'$'))
# 输出
# alex$$$$$$$$$$$$$$$$
源码：
1 def ljust(lf, *args, **kwargs): #real signature unknown
2 """
3 Return a left-justified string of length width.4
5 Padding is done using the specified fill character (default is a space).
6 """
源码
12. rjust 原有字符串在右⽅，左⽅添加指定字符
表达式 str.rjust(width,fillchar) ==> str
width 总格式化宽度
fillchar 插⼊字符
⽰例：
1 print('alex'.rjust(20,'$'))
# 输出
# $$$$$$$$$$$$$$$$alex
源码：
1 def rjust(lf, *args, **kwargs): #real signature unknown
2 """
