Table of Contents

• More on Strings
  • Advanced String Syntax
    • Escape Characters
    • Raw Strings
    • Multiline Strings with Triple Quotes
    • Similarities Between Strings and Lists
  • String Methods
    • upper(), lower(), title() String Methods
    • isupper() and islower() String Methods
    • isalpha(), isalum(), isdecimal(), isspace(), istitle() String Methods
    • startswith(), endswith() String Methods
    • join() String Method
    • split() String Method
    • ljust(), rjust(), center() String Methods
    • strip(), rstrip(), lstrip() String Methods
    • replace() String Method
  • Chaining Methods
  • The pyperclip Module
    • pyperclip.copy(), pyperclip.paste() Functions
  • String Formatting
    • Using Conversion Specifiers %s
    • Using .format() with {}

More on Strings

Advanced String Syntax

Strings can begin and end with either single quote ' ' or double quotes " "

Escape Characters

Escape characters \ let you put quotes and other characters that are hard to type inside strings

# 'That is Alice's cat' # SyntaxError

'That is Alice\'s cat'

"That is Alice's cat"

Escape Character	Prints as
\'	Signle quote
\"	Double quotes
\t	Tab
\n	Newline (line break)
\	Backslash

Raw Strings

Raw strings r' ' will literally print any backslash \ in the string and ignore escape characters

r'That is Carol\'s cat.'

"That is Carol\\'s cat."

print(r'That is Carol\'s cat.')

That is Carol\'s cat.

Multiline Strings with Triple Quotes

Multiline strings start and end with three quotes ''' or """, and can span multiple lines.

print("""Dear Alice,
Eve's cat has been arrested for catnapping
Sincerely,
Bob.""")

Dear Alice,
Eve's cat has been arrested for catnapping
Sincerely,
Bob.

spam = """Dear Alice,
Eve's cat has been arrested for catnapping
Sincerely,
Bob."""

spam

"Dear Alice,\nEve's cat has been arrested for catnapping\nSincerely,\nBob."

Similarities Between Strings and Lists

Indexes, slices, and the in and not in operators all work with strings

spam = 'Hello world!'
spam[0]

'H'

spam[1:5]

'ello'

spam[-1]

'!'

'Hello' in spam

True

'HELLO' in spam

False

'x' in spam

False

String Methods

Since strings are immutable, string methods return a new string value rather than modifying string in place

upper(), lower(), title() String Methods

Recall strings are immutable

spam = 'Hello World'
spam.upper()
spam

'Hello World'

The upper() method returns an uppercase

spam = spam.upper()
spam

'HELLO WORLD'

The lower() method returns s lowercase string

spam.lower()

'hello world'

The title() method returns a title case string.

'hello world'.title()

'Hello World'

isupper() and islower() String Methods

The isupper(), islower() methods return boolean value (True or False) if the string is that respective kind of string

spam = 'Hello World'
spam.islower()

False

spam = 'HELLO WORLD'
spam.isupper()

True

spam = ''
spam.isupper()

False

spam.islower()

False

isalpha(), isalum(), isdecimal(), isspace(), istitle() String Methods

The isalpha(), isalum(), isdecimal(), isspace(), istitle() methods return boolean value (True or False) if the string is that respective kind of string

Method	Desc
isalpha()	letters only
isalnum()	letters and numbers only
isdecimal()	numbers only
isspace()	whitespace only
istitle()	titlecase only

'hello'.isalpha()

True

'hello123'.isalpha()

False

'hello123'.isalnum()

True

'132'.isdecimal()

True

'     '.isspace()

True

'Hello World'.isspace()

False

'Hello World'[5].isspace()

True

'This Is Title Case'.istitle()

True

startswith(), endswith() String Methods

The startswith(), endswith() methods return boolean values

'Hello world'.startswith('H')

True

'Hello world'.startswith('el')

False

'Hello world'.endswith('world')

True

'Hello world'.endswith('a')

False

join() String Method

The join method returns a string that combines the strings in a list

','.join(['cats', 'rats', 'bats'])

'cats,rats,bats'

' '.join(['cats', 'rats', 'bats'])

'cats rats bats'

'\n\n'.join(['cats', 'rats', 'bats'])

'cats\n\nrats\n\nbats'

print('\n\n'.join(['cats', 'rats', 'bats']))

cats

rats

bats

split() String Method

The split() method returns a list of strings, split from the string it's called on

'My name is Simon'.split()

['My', 'name', 'is', 'Simon']

'My name is Simon'.split('m')

['My na', 'e is Si', 'on']

ljust(), rjust(), center() String Methods

The ljust(), rjust(), center() methods return a string padded with spaces

'Hello'.rjust(10)

'     Hello'

len('     Hello')

10

'Hello'.ljust(10) # 'Hello     '

'Hello     '

'Hello'.rjust(10, '*')

'*****Hello'

'Hello'.center(10)

'  Hello   '

'Hello'.center(10, '=')

'==Hello==='

strip(), rstrip(), lstrip() String Methods

The strip(), rstrip(), lstrip() methods return a string with whitespace stripped off the sides

spam = 'Hello'.rjust(10)
spam

'     Hello'

spam.strip()

'Hello'

'    x    '.strip()

'x'

'    x    '.rstrip()

'    x'

'    x    '.lstrip()

'x    '

'SpamSpamBaconSpamEggs'.strip('ampS')

'BaconSpamEggs'

replace() String Method

The replace() method will replace all occurrences of the first string argument with the second string argument

'Hello there'.replace('e', 'XYZ')

'HXYZllo thXYZrXYZ'

Chaining Methods

'Hello'.upper().isupper()

True

The pyperclip Module

The pyperclip module has copy() and paste() functions for using the clipboard

Check if pyperclip is installed

import pyperclip

pyperclip.copy(), pyperclip.paste() Functions

import pyperclip
pyperclip.copy('Hello') # to clipboard
pyperclip.paste()

'Hello'

String Formatting

Using Conversion Specifiers %s

name = 'Alice'
place = 'Main Street'
time = '6 pm'
food = 'turnips'

print("""Hello %s, you are invite to s party at %s
at %s. Please bring %s.""" %(name, place, time, food))

Hello Alice, you are invite to s party at Main Street
at 6 pm. Please bring turnips.

Using .format() with {}

name = 'Sam'
print('hello {}'.format(name))

hello Sam

name = 'John'
age = 12
print('Hi my name is {y} and my age is {x}'.format(x=age, y=name))

Hi my name is John and my age is 12