Summary: in this tutorial, you’ll learn how to use the Python string isalpha()
method to check if all characters in a string are alphabetic.
Introduction to the Python string isalpha() method
The string isalpha()
method returns True
if:
- the string contains only alphabetic characters
- and the string has at least one character.
Otherwise, the isalpha()
method returns False
.
The following shows the syntax of the isalpha()
method:
str.isalpha()
Code language: CSS (css)
Note that alphabetic characters are characters defined as letters in the Unicode character database.
Python string isalpha() method examples
The following example uses the isalpha()
method to check if a string contains alphabetic characters:
name = 'John'
print(name.isalpha())
Code language: PHP (php)
Output:
True
Code language: PHP (php)
It returned True
because the string 'John'
contains only alphabetic characters.
The following example returns False
because the string 'Jane Doe'
contains a space:
name = 'Jane Doe'
print(name.isalpha())
Code language: PHP (php)
Output:
False
Code language: PHP (php)
In general, if the string contains whitespace, the isalpha()
method returns False
.
The following example uses the isalpha()
method to check if all the characters in the string 'Python3'
are alphabetic. It returns False
because the string contains a number:
s = 'Python3'
print(s.isalpha())
Code language: PHP (php)
Output:
False
Code language: PHP (php)
The following example returns False becuase the string is empty:
empty = ''
print(empty.isalpha())
Code language: PHP (php)
Output:
False
Code language: PHP (php)
Summary
- Use the Python string
isalpha()
method to check if all characters in a string are alphabetic.