Python String Method Learning notes

# One, string case conversion
# string First character uppercase
Print ("Hello World". Capitalize ())
# Change a string to a title
Print ("Hello World". Title ())
# Convert String to uppercase
Print ("Hello World". Upper ())
# Convert String to lowercase
Print ("HELLO World". Lower ())
# Flip the case in a string
Print ("Hello World". Swapcase ())

# Two, string segmentation
# with an element as a split point, divide the string into 3 parts, and the first element found from left to right is a split point
Print (' HelloWorld '. partition (' O '))
# divides a string into 3 parts with an element as a split point, and the first element found from right to left is a split point
Print (' HelloWorld '. rpartition (' O '))
# Replace the elements in the original string, replace all by default, you can specify a few (left to right number)
Print ("Hello World". Replace (' O ', ' a ', 1))
# Divide a string by dividing it from left to right by dividing it by a single element.
Print ("Hello World". Split (' O ', 1))
# Divide a string by dividing it from right to left n times with an element as a split point
Print ("Hello World". Rsplit (' O ', 1))
# Separated by line (' \ r ', ' \ r \ n ', \ nthe '), returns a list containing the rows as elements, if the argument keepends is False, does not contain a newline character, and if true, the newline character is preserved.
Print (' Hello\nworld '. Splitlines (True))
# Three, find elements in a string
# count the number of occurrences of a string from index n to y, by default to find in the entire string
Print ("Hello World". Count (' O ', 7, 10))
# finds an element between index [n, y] and defaults to [:] Returns the index of the element if no return-1 is found
Print ("Hello World". Find (' e '))
Print ("Hello World". Find (' O ', 0, 2))
# The index value of the element is found between [N, y] and no error is found
Print ("Hello World". Index (' o '))
Print ("Hello World". Index (' e ', 0, 5))
# Four, string judgment
# Determines whether a string starts with an element
Print (' HelloWorld '. StartsWith (' h '))
# Determines whether the string's index from [N,y] ends with a character and returns a Boolean value
Print ("Hello World". EndsWith (' E ', 0, 2))
# Determine if there are only numbers or letters
Print (' abc123 '. Isalnum ())
# to determine if it contains only letters
Print (' abc '. ISALPHA ())
# Determine if the letters are lowercase
Print ("Hello". Islower ())
# Determine if character is not a space
Print ("". Isspace ())
# determine if the string is not a caption (the first letter is not uppercase)
Print ("Hello World". Istitle ())
# inserts a specified character between elements
# Five, string formatting
# Center String, specify the total length of the string, not enough with other characters, the default is a space
Print ("Hello World". Center (20, "#"))
# replace \ t in string with n spaces
Print ("Hello\tworld". Expandtabs (TABSIZE=20))
Print (' # '. Join ("Hello World"))
# Specify the length of the output character, and left-aligned, the less part with the specified characters
Print ("Hello World". Ljust (20, "#"))
# Specify the length of the output character, and right-aligned, the less part with the specified characters
Print ("Hello World". Rjust (20, "#"))
# Remove the space to the left of the string
Print (' Hello '. Lstrip ())
# Remove the space to the right of the string
Print (' Hello '. Rstrip ())
# remove spaces on both sides of the string
Print (' Hello '. Strip ())
# Specifies the length of the string, not enough in front of the complement 0
Print ("123". Zfill (5))
# Concatenation of strings
Print (' Hello ' + ' world ')
Print (' Hello ' * 3)

Python String Method Learning notes