Python File Reading Examples

Introduction

Reading files is one of the most common operations in Python programming. Python provides easy-to-use methods for reading entire files, reading line by line, and more.

Below are 10 examples to help you understand different ways to read files in Python with detailed explanations.

10 Examples of Reading Files in Python

Example 1: Read Entire File Using read()

file = open('sample.txt', 'r')
content = file.read()
print(content)
file.close()

Output:
Prints entire content of 'sample.txt'.

This opens 'sample.txt' in read mode, reads all content at once, prints it, and closes the file.

Example 2: Read File Line by Line Using readline()

file = open('sample.txt', 'r')
line1 = file.readline()
line2 = file.readline()
print(line1)
print(line2)
file.close()

Output:
Prints first two lines of the file separately.

Reads first line and second line individually using readline() and prints them.

Example 3: Read All Lines as a List Using readlines()

file = open('sample.txt', 'r')
lines = file.readlines()
print(lines)
file.close()

Output:
Prints a list of all lines with newline characters.

Reads all lines and returns them as a list of strings, then prints the list.

Example 4: Iterate Over File Object Line by Line

file = open('sample.txt', 'r')
for line in file:
    print(line.strip())
file.close()

Output:
Prints each line after removing leading/trailing spaces.

Iterates over the file object directly, printing each line with whitespace stripped.

Example 5: Using with Statement to Read Entire File

with open('sample.txt', 'r') as file:
    content = file.read()
    print(content)

Output:
Prints entire file content safely without explicit close.

'with' statement handles closing file automatically after reading all content.

Example 6: Using with Statement to Read Line by Line

with open('sample.txt', 'r') as file:
    for line in file:
        print(line.strip())

Output:
Prints each line without extra spaces safely.

Reads file line by line inside 'with' block, stripping spaces and printing.

Example 7: Reading Large Files in Chunks

with open('sample.txt', 'r') as file:
    while True:
        chunk = file.read(50)  # reads 50 characters
        if not chunk:
            break
        print(chunk)

Output:
Reads and prints file content in chunks of 50 characters.

Useful for large files, reads fixed-size chunks to avoid loading entire file at once.

Example 8: Reading Binary File

with open('image.png', 'rb') as file:
    content = file.read(100)
    print(content)

Output:
Prints first 100 bytes of binary file (image.png).

Reads first 100 bytes of a binary file in binary mode 'rb'.

Example 9: Reading File with Specified Encoding

with open('utf8file.txt', 'r', encoding='utf-8') as file:
    content = file.read()
    print(content)

Output:
Reads UTF-8 encoded text file properly.

Specifies encoding while opening to correctly read files with special characters.

Example 10: Using try-except for File Reading Errors

try:
    with open('missing.txt', 'r') as file:
        content = file.read()
        print(content)
except FileNotFoundError:
    print('File not found!')

Output:
Prints error message if file does not exist.

Handles file not found error gracefully using try-except.