Does Python have a string 'contains' substring method?
Python doesn't have a dedicated contains() method for strings, but you can easily check substrings using alternatives like the in operator or the find() method. Learn how to perform substring checks effectively in Python!
No, Python doesn’t have a built-in contains() method for strings, which can surprise those coming from other programming languages. However, Python provides several simple and effective ways to check if a string contains a substring.
Here are some alternatives you can use:
Using the in operator (most common and readable)
This is the Pythonic way to check for substrings. It’s straightforward and easy to understand.
text = "Hello, world!"
if "world" in text:
print("Substring found!")
Using the find() method
The find() method returns the index of the substring if found, or -1 if it’s not present.
text = "Python is fun"
if text.find("fun") != -1:
print("Substring found!")
Using the index() method
Similar to find(), but it raises a ValueError if the substring is not found.
try:
position = text.index("Python")
print("Substring found at index:", position)
except ValueError:
print("Substring not found.")
Using Regular Expressions (for advanced searches)
Regular expressions allow more complex substring matching.
import re
if re.search("Python", text):
print("Substring found!")
- In most cases, the in operator is the best choice due to its simplicity and readability. Python emphasizes clean and readable code, which is why in is often preferred.