Python Strings
In Python, strings are used to store text data.
A string is a sequence of characters enclosed in single quotes, double quotes, or triple quotes.
Strings are one of the most commonly used data types in Python.
What Is a String?
A string is a collection of characters such as:
- Letters
- Numbers
- Symbols
- Spaces
python
text = "Hello Python"
python
name = 'John'
python
message = "Welcome to Python Programming"
Creating Strings in Python
Strings can be created using:
- Single quotes (
' ') - Double quotes (
" ") - Triple quotes (
''' '''or""" """)
Single Quotes
python
language = 'Python'
Double Quotes
python
language = "Python"
Triple Quotes (Multi-line Strings)
python
text = """Python is easy
Python is powerful
Python is popular"""
print(text)
Strings Are Immutable
Strings in Python are immutable, which means they cannot be changed after creation.
python
text = "Python"
# text[0] = "J" # Error
python
text = "Python"
text = "Java"
print(text)
String Indexing
Each character in a string has an index position starting from 0.
python
text = "Python"
print(text[0])
python
print(text[3])
python
print(text[-1])
String Slicing
Slicing is used to extract a portion of a string.
python
text = "Python"
print(text[0:3])
python
print(text[2:5])
python
print(text[:4])
String Length
The
len() function is used to find the length of a string.python
text = "Python"
print(len(text))
python
name = "Programming"
print(len(name))
python
print(len("Hello World"))
String Concatenation
Strings can be joined using the
+ operator.python
a = "Hello"
b = "Python"
print(a + " " + b)
python
first = "Code"
second = "Marathi"
print(first + second)
python
print("AWS" + " Cloud")
String Repetition
Strings can be repeated using the
* operator.python
print("Python " * 3)
python
star = "*"
print(star * 10)
python
print("Hi " * 2)
String Formatting
Using Comma
python
name = "John"
age = 25
print("Name:", name, "Age:", age)
Using f-strings (Recommended)
python
name = "John"
age = 25
print(f"Name is {name} and age is {age}")
python
a = 5
b = 10
print(f"Sum is {a + b}")
Common String Methods
python
text = "python"
print(text.upper())
python
print(text.lower())
python
print(text.capitalize())
python
print(text.replace("p", "P"))
Checking Substrings
python
text = "Python Programming"
print("Python" in text)
python
print("Java" in text)
python
print("gram" in text)
Summary
- Strings store text data
- Strings are immutable
- Indexing starts from 0
- Slicing extracts parts of a string
len()finds string length- Strings support many useful methods
Exercise
- Create a string and print its length
- Extract first three characters
- Convert a string to uppercase