String Methods

Strings come with a rich toolbox of methods. Here are the ones you'll use most.

Case and spacing

python
s = "  Hello World  "
s.upper()

### '  HELLO WORLD  '
s.lower()

### '  hello world  '
s.strip()

### 'Hello World'
s.capitalize()

### '  Hello world  '
s.title()

### '  Hello World  '
s.swapcase()

### '  hELLO wORLD  '

Search and replace

python
s = "Hello, World!"
s.find("World")

### 7
s.index("World")

### 7
s.count("o")

### 2
s.replace("World", "Python")

### 'Hello, Python!'
s.startswith("He")

### True
s.endswith("!")

### True

Checks (return True or False)

python
s = "123"
s.isalnum()

### True (letters or digits)
s.isalpha()

### False (digits are not letters)
s.isdigit()

### True
s.islower()

### False
s.isupper()

### False
s.isspace()

### False

Split and join

python
"a,b,c".split(",")

### ['a', 'b', 'c']
"-".join(["a", "b"])

### 'a-b'

Padding and centering

python
"42".zfill(5)

### '00042'
"hi".center(6)

### '  hi  '

Remember

Methods return new strings. The original is never modified.

TL;DR

• Case: upper, lower, capitalize, title, swapcase.
• Search: find, index, count, startswith, endswith, replace.
• Checks: isalnum, isalpha, isdigit, islower, isupper.
• Tools: split, join, zfill, center, strip.