String Composition Verification with isOOO() Methods
Functions with names in the form of isOOO() like isalnum(), isalpha(), and isdigit() are used to verify the composition of a string.
These functions check if the characters in a string satisfy certain conditions and return True or False accordingly.
The main functions include:
-
isalnum(): Checks if the string contains only alphabetic characters (A, a, B, b...) and digits (1, 0, 9...) -
isalpha(): Checks if the string consists solely of alphabetic characters -
isdigit(): Checks if all characters in the string are digits (0-9)
Examples using isOOO()
text = "Python3"
print(text.isalnum()) # True
print(text.isalpha()) # False
print(text.isdigit()) # False
When are these functions used?
isOOO() functions are primarily used to validate user input or clean data.
Example of Input Validation
text = input("Please enter your username containing letters or numbers: ")
if text.isalnum():
print("Valid input: The string contains only letters and/or numbers.")
else:
print("Invalid input: The string contains special characters or spaces.")
Want to learn more?
Join CodeFriends Plus membership or enroll in a course to start your journey.