Các phương thức chuỗi (String Methods) trong Python?

>>> mystring = "hello python" >>> print(mystring.capitalize()) Hello python

>>> mystring = "hello PYTHON" >>> print(mystring.casefold()) hello python

>>> mystring = "Hello" >>> x = mystring.center(12, "-") >>> print(x) ---Hello----

>>> mystr = "Hello Python" >>> print(mystr.count("o")) 2 >>> print(mystr.count("th")) 1 >>> print(mystr.count("l")) 2 >>> print(mystr.count("h")) 1 >>> print(mystr.count("H")) 1 >>> print(mystr.count("hH")) 0

>>> mystr = 'python!' >>> print('The string is:', mystr) The string is: python! >>> print('The encoded version is: ', mystr.encode("ascii", "ignore")) The encoded version is: b'python!' >>> print('The encoded version (with replace) is:', mystr.encode("ascii", "replace")) The encoded version (with replace) is: b'python!'

>>> mystr = "Python" >>> print(mystr.endswith("y")) False >>> print(mystr.endswith("hon")) True

>>> mystr = "1\t2\t3" >>> print(mystr) 1 2 3 >>> print(mystr.expandtabs()) 1 2 3 >>> print(mystr.expandtabs(tabsize=15)) 1 2 3 >>> print(mystr.expandtabs(tabsize=2)) 1 2 3

>>> mystring = "Python" >>> print(mystring.find("P")) 0 >>> print(mystring.find("on")) 4

>>> print("{} and {}".format("Apple", "Banana")) Apple and Banana >>> print("{1} and {0}".format("Apple", "Banana")) Banana and Apple >>> print("{lunch} and {dinner}".format(lunch="Peas ", dinner="Beans")) Peas and Beans

>>> lunch = {"Food": "Pizza", "Drink": "Wine"} >>> print("Lunch: {Food}, {Drink}".format_map(lunch)) Lunch: Pizza, Wine >>> class Default(dict): def __missing__(self, key): return key >>> lunch = {"Drink": "Wine"} >>> print("Lunch: {Food}, {Drink}".format_map(Default(lunch))) Lunch: Food, Wine

>>> mystr = "HelloPython" >>> print(mystr.index("P")) 5 >>> print(mystr.index("hon")) 8 >>> print(mystr.index("o")) 4

>>> mystr = "HelloPython" >>> print(mystr.isalnum()) True >>> a = "123" >>> print(a.isalnum()) True >>> a= "$*%!!!" >>> print(a.isalnum()) False

>>> mystr = "HelloPython" >>> print(mystr.isalpha()) True >>> a = "123" >>> print(a.isalpha()) False >>> a= "$*%!!!" >>> print(a.isalpha()) False

>>> mystr = "HelloPython" >>> print(mystr.isdecimal()) False >>> a="1.23" >>> print(a.isdecimal()) False >>> c = u"\u00B2" >>> print(c.isdecimal()) False >>> c="133" >>> print(c.isdecimal()) True

>>> c="133" >>> print(c.isdigit()) True >>> c = u"\u00B2" >>> print(c.isdigit()) True >>> a="1.23" >>> print(a.isdigit()) False

>>> c="133" >>> print(c.isidentifier()) False >>> c="_user_123" >>> print(c.isidentifier()) True >>> c="Python" >>> print(c.isidentifier()) True

>>> c="Python" >>> print(c.islower()) False >>> c="_user_123" >>> print(c.islower()) True >>> print(c.islower()) False

>>> c="133" >>> print(c.isnumeric()) True >>> c="_user_123" >>> print(c.isnumeric()) False >>> c="Python" >>> print(c.isnumeric()) False

>>> c="133" >>> print(c.isprintable()) True >>> c="_user_123" >>> print(c.isprintable()) True >>> c="\t" >>> print(c.isprintable()) False

>>> c="133" >>> print(c.isspace()) False >>> c="Hello Python" >>> print(c.isspace()) False >>> c="Hello" >>> print(c.isspace()) False >>> c="\t" >>> print(c.isspace()) True

>>> c="133" >>> print(c.istitle()) False >>> c="Python" >>> print(c.istitle()) True >>> c="\t" >>> print(c.istitle()) False

>>> c="Python" >>> print(c.isupper()) False >>> c="PYHTON" >>> print(c.isupper()) True >>> c="\t" >>> print(c.isupper()) False

>>> a ="-" >>> print(a.join("123")) 1-2-3 >>> a="Hello Python" >>> a="**" >>> print(a.join("Hello Python")) H**e**l**l**o** **P**y**t**h**o**n

>>> a="Hello" >>> b = a.ljust(12, "_") >>> print(b) Hello_______

>>> a = "Python" >>> print(a.lower()) python

>>> a = " Hello " >>> print(a.lstrip(), "!") Hello !

>>> frm = "SecretCode" >>> to = "4203040540" >>> trans_table = str.maketrans(frm,to) >>> sec_code = "Secret Code".translate(trans_table) >>> print(sec_code) 400304 0540

>>> mystr = "Hello-Python" >>> print(mystr.partition("-")) ('Hello', '-', 'Python') >>> print(mystr.partition(".")) ('Hello-Python', '', '')

>>> mystr = "Hello Python. Hello Java. Hello C++." >>> print(mystr.replace("Hello", "Bye")) Bye Python. Bye Java. Bye C++. >>> print(mystr.replace("Hello", "Hell", 2)) Hell Python. Hell Java. Hello C++.

>>> mystr = "Hello-Python" >>> print(mystr.rfind("P")) 6 >>> print(mystr.rfind("-")) 5 >>> print(mystr.rfind("z")) -1

>>> mystr = "Hello-Python" >>> print(mystr.rindex("P")) 6 >>> print(mystr.rindex("-")) 5 >>> print(mystr.rindex("z")) Traceback (most recent call last): File "<pyshell#253>", line 1, in <module> print(mystr.rindex("z")) ValueError: substring not found

>>> mystr = "Hello Python" >>> mystr1 = mystr.rjust(20, "-") >>> print(mystr1) --------Hello Python

>>> mystr = "Hello Python" >>> print(mystr.rpartition(".")) ('', '', 'Hello Python') >>> print(mystr.rpartition(" ")) ('Hello', ' ', 'Python')

>>> mystr = "Hello Python" >>> print(mystr.rsplit()) ['Hello', 'Python'] >>> mystr = "Hello-Python-Hello" >>> print(mystr.rsplit(sep="-", maxsplit=1)) ['Hello-Python', 'Hello']

>>> mystr = "Hello Python" >>> print(mystr.rstrip(), "!") Hello Python ! >>> mystr = "------------ Hello Python-----------" >>> print(mystr.rstrip("-")) ------------Hello Python >>> print(mystr.rstrip("_")) ------------Hello Python----------- _

>>> mystr = "Hello Python" >>> print(mystr.split()) ['Hello', 'Python'] >>> mystr1="Hello,,Python" >>> print(mystr1.split(",")) ['Hello', '', 'Python']

>>> mystr = "Hello:\n\n Python\r\nJava\nC++\n" >>> print(mystr.splitlines()) ['Hello:', '', ' Python', 'Java', 'C++'] >>> print(mystr.splitlines(keepends=True)) ['Hello:\n', '\n', ' Python\r\n', 'Java\n', 'C++\n']

>>> mystr = "Hello Python" >>> print(mystr.startswith("P")) False >>> print(mystr.startswith("H")) True >>> print(mystr.startswith("Hell")) True

>>> mystr = " Hello Python " >>> print(mystr.strip(), "!") Hello Python ! >>> print(mystr.strip()) Hello Python

>>> mystr = "Hello PYthon" >>> print(mystr.swapcase()) hELLO python

>>> mystr = "Hello PYthon" >>> print(mystr.title()) Hello Python >>> mystr = "HELLO JAVA" >>> print(mystr.title()) Hello Java

>>> frm = "helloPython" >>> to = "40250666333" >>> trans_table = str.maketrans(frm, to) >>> secret_code = "Secret Code".translate(trans_table) >>> print(secret_code) S0cr06 C3d0

>>> mystr = "hello Python" >>> print(mystr.upper()) HELLO PYTHON

>>> mystr = "999" >>> print(mystr.zfill(9)) 000000999 >>> mystr = "-40" >>> print(mystr.zfill(5)) -0040