Reading a file line by line in Python is straightforward and can be done using various methods. Below are some common approaches:
1. Using a for Loop
This is the most Pythonic way to read a file line by line.
2. Using readline()
The readline() method reads one line at a time. You can use it in a loop.
3. Using readlines()
The readlines() method reads all lines at once and returns them as a list. This can be useful for smaller files.
4. Using fileinput (for Multiple Files)
The fileinput module allows you to read from multiple files line by line.
5. Efficient Reading for Large Files
For large files, reading line by line (using a for loop) is memory efficient because it doesn’t load the entire file into memory.
Notes:
- Always use
with open()to handle files, as it ensures the file is properly closed after use. - Use
strip()to remove newline characters (\n) or extra spaces at the ends of lines. - Replace
'filename.txt'with the path to your file.