Strings

Strings are sequences of characters. In Python, strings are Unicode by default, so they can represent text from many languages.

Creating Strings

single = 'Hello'
double = "Hello"
multi = """Hello,
world"""

Indexing and Slicing

text = "Python"

print(text[0])    # P
print(text[-1])   # n
print(text[1:4])  # yth

Slicing is start inclusive and end exclusive.

Immutability

Strings are immutable, so you cannot change a character in place.

text = "Hello"
# text[0] = "J"  # TypeError

Common Operations

greeting = "Hello" + " " + "World"
echo = "Hi" * 3

Membership and Iteration

if "World" in greeting:
    print("Found")

for ch in "Hi":
    print(ch)

Formatting

Use f-strings for most cases:

name = "Ada"
age = 28
print(f"{name} is {age} years old.")

str.format() is also common:

print("{} {}".format("Hello", "World"))

Useful Methods

text = "  Hello World  "

print(text.lower())
print(text.upper())
print(text.strip())
print(text.replace("World", "Python"))
print(text.split())

Next | Previous