python學習--13 基本數據類型 2

接上次補充：

s = "username\temail\tpassword\naaa\taa@qq.com\t123\nusername\temail\tpassword\naaa\taa@qq.com\t123"
a = s.expandtabs(20)    #斷句，以20爲單位，不夠就自動補齊20個
print(a)

運算結果：

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

Process finished with exit code 0

其餘功能：

1.

#判斷當前輸入是否爲數字
test = '②'
a1 = test.isdecimal()          #僅支持數字
a2 = test.isdigit()           #支持特殊符號和數字
a3 = test.isnumeric()         #支持全部包括中文
print(a1,a2,a3)

運算結果：

False True True

Process finished with exit code 0

2.

test = 'sjalfaj\tafaaf'
a1 = test.isprintable()          # 是否存在不可顯示的字符
print(a1)

運算結果：

False

Process finished with exit code 0

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

運算結果：

True

Process finished with exit code 0

3.判斷字符串裏是否全是空格

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

運算結果：

False

Process finished with exit code 0

4.判斷是不是標題（首字母大寫）

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

運算結果：

False

Process finished with exit code 0

5.變成標題

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

運算結果：

False
Sjalfa   Jafaaf

Process finished with exit code 0

6.

#將字符串中的每個元素按照指定分隔符進行拼接
test = '你好啊豬頭'
print(test)
t = ' '
a = t.join(test)        #或者 把t.join(test)改爲' '.join(test)
print(a)

運算結果：

你好啊豬頭
你 好 啊 豬 頭

Process finished with exit code 0

7.填充

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

運算結果：

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)

運算結果：

0000000000000000abcd

Process finished with exit code 0

9.

test = 'ABCD'
a = test.islower()      # 判斷是否爲小寫
a1 = test.lower()       # 所有變成小寫

print(a,a1)

運算結果：

False abcd

Process finished with exit code 0

10.

test = 'abcd'
a = test.isupper()      # 判斷是否爲大寫
a1 = test.upper()       #變成大寫

print(a,a1)

運算結果：

False ABCD

Process finished with exit code 0

11.去掉空白（換行\n，空格\t也能去掉）

test = '   abcd    '
a = test.lstrip()     # 去掉左邊空白
#a1 = test.rstrip()       #去掉右邊空白
#a2 = test.strip()     # 去掉所有空白
print(a)

12.移除指定字符串 

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

print(a)

運算結果：

bcd

Process finished with exit code 0

13.分割

test = 'lovesdcvvf'
a = test.partition('v')         #只能將整個字符串分割成3份
a1 = test.rpartition('v')         #從右開始分割成3份
a2 =test.split("v",2)              #所有分割
a3 = test.rsplit()                  #從右開始所有分割
print(a)
print(a1)
print(a2)
print(a3)

運算結果：

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

Process finished with exit code 0

14.

test = 'adfsdf\nsafafsad\ndsaf'
a = test.splitlines(True)           # 只能根據換行分割，  布爾值用來是否顯示換行符
print(a)

運算結果：

['adfsdf\n', 'safafsad\n', 'dsaf']

Process finished with exit code 0

15.

test = 'adfsdf\nsafafsad\ndsaf'
a = test.startswith('a')        #判斷是否以a開頭的
b = test.endswith("a")          #判斷是否以a結尾
print(a)
print(b)

運算結果：

True
False

Process finished with exit code 0

16.大小寫轉換

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

運算結果：

ABC

Process finished with exit code 0