String in python
A string is a collection of text. Anything in Python surrounded by ‘’ or “” is called a string.
Single line strings are surrounded by single or double commas while we can write
multiline strings as well using triple commas
x = ‘single line string’
x = “single line string”
y = ”’multiline string
multiline string ”’
Example
name = “Python”
print(name)
message = “I love Python.”
print(message)
Indexing: One way is to treat strings as a list and use index values. For example,
greet = ‘hello’
print(greet[1]) – e
Negative Indexing: Similar to a list, Python allows negative indexing for its strings. For example,
greet = ‘hello’
print(greet[-4]) – e
Slicing: Access a range of characters in a string by using the slicing operator colon : For example
a = “Hello”
print(a[1:5])
String length
a = “Hello, World!”
print(len(a))
IN keyword
………………
txt = “The best things in life are free!”
print(“free” in txt)
………………..
txt = “The best things in life are free!”
if “free” in txt:
print(“Yes, ‘free’ is present.”)
…………
txt = “The best things in life are free!”
print(“expensive” not in txt)
Python String Operations
Comparison
str1 = “Hello, world!”
str2 = “I love Python.”
str3 = “Hello, world!”
print(str1 == str2)
print(str1 == str3)
Join Two or More Strings
greet = “Hello, ”
name = “Ali”
result = greet + name
print(result)
……….
We can iterate through a string using a for loop. For example,
a= ‘Hello’
for letter in a:
print(letter)
Python String Formatting
name = ‘ahmad’
country = ‘UAE’
print(f'{name} is from {country}’)
Methods of python string
Methods Description
upper() converts the string to uppercase
lower() converts the string to lowercase
partition() returns a tuple
replace() replaces substring inside
find() returns the index of first occurrence of substring
rstrip() removes trailing characters
split() splits string from left
startswith() checks if string starts with the specified string
isnumeric() checks numeric characters
index() returns index of substring
