6 Python RegEx
1. What is RegEx?
RegEx means Regular Expression.
In simple words:
👉 RegEx is used to search, match, or change text
👉 It helps us find patterns in strings
Examples:
-
Find email addresses
-
Check phone numbers
-
Search words in a sentence
2. RegEx Module in Python
Python has a built-in module called re.
Import RegEx Module
3. Simple RegEx Example (Search Word)
Example
4. findall() – Find All Matches
Example
5. search() – Search First Match
Example
6. split() – Split String Using RegEx
Example
7. sub() – Replace Text
Example
8. Common RegEx Patterns (Easy)
| Pattern | Meaning |
|---|---|
[a-z] |
small letters |
[A-Z] |
capital letters |
[0-9] |
numbers |
. |
any character |
^ |
starts with |
$ |
ends with |
* |
zero or more |
+ |
one or more |
9. Check Starts With Word
Example
10. Check Ends With Word
Example
11. Validate Email (Simple)
Example
12. RegEx Flags (Ignore Case)
Example
13. Common Beginner Mistakes
❌ Forgetting Raw String
✔ Better:
❌ Using Wrong Escape
✔ Correct:
14. Simple Practice Examples
Example 1: Find Digits
Example 2: Replace Spaces
Example 3: Check Phone Number
15. Summary (Python RegEx)
✔ Used to find text patterns
✔ Uses re module
✔ findall(), search(), split(), sub()
✔ Very useful for validation
✔ Powerful but needs practice
📘 Perfect for Beginner eBook
This chapter is ideal for:
-
Python beginner books
-
School & college students
-
Self-learners
If you want next, I can write:
-
RegEx Exercises
-
File Handling
-
Exception Handling
-
Web Scraping (basic)
-
Mini Python Projects
Just tell me 😊
