python学习--13 基本数据类型 2

接上次补充：

s = "username	email	password
aaa	aa@qq.com	123
username	email	password
aaa	aa@qq.com	123"
a = s.expandtabs(20)    #断句，以20为单位，不够就自动补齐20个
print(a)

运算结果：

username            email               password
aaa                 aa@qq.com           123
username            email               password
aaa                 aa@qq.com           123

Process finished with exit code 0

其他功能：

1.

#判断当前输入是否为数字
test = '②'
a1 = test.isdecimal()          #仅支持数字
a2 = test.isdigit()           #支持特殊符号和数字
a3 = test.isnumeric()         #支持所有包括中文
print(a1,a2,a3)

运算结果：

False True True

Process finished with exit code 0

2.

test = 'sjalfaj	afaaf'
a1 = test.isprintable()          # 是否存在不可显示的字符
print(a1)

运算结果：

False

Process finished with exit code 0

test = 'sjalfajafaaf'
a1 = test.isprintable()          # 是否存在不可显示的字符
print(a1)

运算结果：

True

Process finished with exit code 0

3.判断字符串里是否全是空格

test = 'sjalfa   jafaaf'
a1 = test.isspace()          # 是否全是空格
print(a1)

运算结果：

False

Process finished with exit code 0

4.判断是否是标题（首字母大写）

test = 'sjalfa   jafaaf'
a1 = test.istitle()         
print(a1)

运算结果：

False

Process finished with exit code 0

5.变成标题

test = 'sjalfa   jafaaf'
a1 = test.istitle()
a2 = test.title()
print(a1)
print(a2)

运算结果：

False
Sjalfa   Jafaaf

Process finished with exit code 0

6.

#将字符串中的每一个元素按照指定分隔符进行拼接
test = '你好啊猪头'
print(test)
t = ' '
a = t.join(test)        #或者 把t.join(test)改成' '.join(test)
print(a)

运算结果：

你好啊猪头
你 好 啊 猪 头

Process finished with exit code 0

7.填充

test = 'abcd'
a = test.ljust(20,'*')          
a1 = test.center(20,'中')
print(a)
print(a1)

运算结果：

abcd****************
中中中中中中中中abcd中中中中中中中中

Process finished with exit code 0

8.只用00填充

test = 'abcd'
a = test.zfill(20)

print(a)

运算结果：

0000000000000000abcd

Process finished with exit code 0

9.

test = 'ABCD'
a = test.islower()      # 判断是否为小写
a1 = test.lower()       # 全部变成小写

print(a,a1)

运算结果：

False abcd

Process finished with exit code 0

10.

test = 'abcd'
a = test.isupper()      # 判断是否为大写
a1 = test.upper()       #变成大写

print(a,a1)

运算结果：

False ABCD

Process finished with exit code 0

11.去掉空白（换行 ，空格 也能去掉）

test = '   abcd    '
a = test.lstrip()     # 去掉左边空白
#a1 = test.rstrip()       #去掉右边空白
#a2 = test.strip()     # 去掉全部空白
print(a)

12.移除指定字符串 

test = 'abcd'
a = test.lstrip("a")

print(a)

运算结果：

bcd

Process finished with exit code 0

13.分割

test = 'lovesdcvvf'
a = test.partition('v')         #只能将整个字符串分割成3份
a1 = test.rpartition('v')         #从右开始分割成3份
a2 =test.split("v",2)              #全部分割
a3 = test.rsplit()                  #从右开始全部分割
print(a)
print(a1)
print(a2)
print(a3)

运算结果：

('lo', 'v', 'esdcvvf')
('lovesdcv', 'v', 'f')
['lo', 'esdc', 'vf']
['lovesdcvvf']

Process finished with exit code 0

14.

test = 'adfsdf
safafsad
dsaf'
a = test.splitlines(True)           # 只能根据换行分割，  布尔值用来是否显示换行符
print(a)

运算结果：

['adfsdf
', 'safafsad
', 'dsaf']

Process finished with exit code 0

15.

test = 'adfsdf
safafsad
dsaf'
a = test.startswith('a')        #判断是否以a开头的
b = test.endswith("a")          #判断是否以a结尾
print(a)
print(b)

运算结果：

True
False

Process finished with exit code 0

16.大小写转换

test = 'abc'
a = test.swapcase()
print(a)

运算结果：

ABC

Process finished with exit code 0