Python re.finditer() Method
Python re Modulere.finditer()is a Pythonremodule function foriteratively finding all matches.
It returns an iterator, where each element is a match object, allowing you to process the matching results one by one.
Term Definition： find iterIt means "find iterator".
Basic Syntax and Parameters
Syntax Format
re.finditer(pattern, string, flags=0)
Parameter Description
- pattern: Regular expression pattern
- string: The string to be searched
- flags: Optional, regular expression flags
Function Description
- Return Value: Returns an iterator, where each element is a match object.
- Features: Suitable for processing large numbers of match results, saving memory.
Examples
Example 1: Basic Usage
Example
import re
text = "3 apples, 5 oranges, 8 bananas"
# Iterate to find all numbers
for match in re.finditer(r'\d+', text):
print(f"Found: {match.group()} Position: {match.start()}-{match.end()}")
text = "3 apples, 5 oranges, 8 bananas"
# Iterate to find all numbers
for match in re.finditer(r'\d+', text):
print(f"Found: {match.group()} Position: {match.start()}-{match.end()}")
Expected output:
找到: 3 位置: 0-1 找到: 5 位置: 4-5 找到: 8 位置: 8-9
Example 2: Processing Email List
Example
import re
text = "Contact test@example.com or admin@test.org for help"
# Find and process each email
for match in re.finditer(r'(\w+)@(\w+\.\w+)', text):
print(f"Full: {match.group()}")
print(f" Username: {match.group(1)}")
print(f" Domain: {match.group(2)}")
print(f" Position: {match.start()}-{match.end()}")
text = "Contact test@example.com or admin@test.org for help"
# Find and process each email
for match in re.finditer(r'(\w+)@(\w+\.\w+)', text):
print(f"Full: {match.group()}")
print(f" Username: {match.group(1)}")
print(f" Domain: {match.group(2)}")
print(f" Position: {match.start()}-{match.end()}")
Expected output:
完整: test@example.com 用户名: test 域名: example.com 位置: 2-16 完整: admin@test.org 用户名: admin 域名: test.org 位置: 17-30
Example 3: Comparison with re.findall()
Example
import re
text = "a1b2c3d4"
# findall returns a list of strings
print("findall:", re.findall(r'\d', text))
# finditer returns an iterator
print("finditer:", [m.group() for m in re.finditer(r'\d', text)])
text = "a1b2c3d4"
# findall returns a list of strings
print("findall:", re.findall(r'\d', text))
# finditer returns an iterator
print("finditer:", [m.group() for m in re.finditer(r'\d', text)])
Expected output:
findall: ['1', '2', '3', '4'] finditer: ['1', '2', '3', '4']
Other Extensions