Python File Handling Exercises

try:
    with open("sample.txt", 'r') as file:
        content = file.read()
        print(content)
except FileNotFoundError:
    print("Error: 'sample.txt' not found.")Code language: Python (python)

try:
    with open("sample.txt", 'r') as file:
        for line in file:
            print(line, end='') # The 'end=''' prevents extra newline characters
except FileNotFoundError:
    print("Error: 'sample.txt' not found.")Code language: Python (python)

try:
    with open("sample.txt", 'r') as file:
        for i in range(5):
          print(file.readline().strip())
except FileNotFoundError:
    print("Error: 'sample.txt' not found.")Code language: Python (python)

import re
def count_words(filename):
    try:
        with open(filename, 'r') as file:
            content = file.read().lower()
            words = re.findall(r'\b\w+\b', content) # Use regex to find whole words
            return len(words)
    except FileNotFoundError:
        return f"Error: '{filename}' not found."
# Example usage:
word_count = count_words("sample.txt")
print(f"Total words in 'sample.txt': {word_count}")Code language: Python (python)

# Solution:
def count_characters(filename):
    try:
        with open(filename, 'r') as file:
            content = file.read()
            return len(content)
    except FileNotFoundError:
        return f"Error: '{filename}' not found."
# Example usage:
char_count = count_characters("sample.txt")
print(f"Total characters in 'sample.txt': {char_count}")Code language: Python (python)

def count_specific_word(filename, word):
    try:
        with open(filename, 'r') as file:
            content = file.read().lower()
            words = content.split()
            count = 0
            for w in words:
                # Remove punctuation to ensure accurate matching
                cleaned_word = w.strip('.,!?"\'()[]{};:')
                if cleaned_word == word.lower():
                    count += 1
            return count
    except FileNotFoundError:
        return f"Error: '{filename}' not found."
# Example usage:
filename = "sample.txt"
word_to_count = "the"
occurrences = count_specific_word(filename, word_to_count)
print(f"The word '{word_to_count}' appears {occurrences} times in '{filename}'.")Code language: Python (python)

filename = "output.txt"
text_to_write = "Hello, PYnative!"
try:
    with open(filename, 'w') as file:
        file.write(text_to_write)
    print(f"Successfully wrote '{text_to_write}' to '{filename}'.")
except Exception as e:
    print(f"An error occurred: {e}")Code language: Python (python)

filename = "output.txt"
text_to_append = "This is an appended line."
try:
    with open(filename, 'a') as file:
        file.write("\n" + text_to_append) # Adding a newline character for better readability
    print(f"Successfully appended '{text_to_append}' to '{filename}'.")
except FileNotFoundError:
    print(f"Error: '{filename}' not found.")
except Exception as e:
    print(f"An error occurred: {e}")Code language: Python (python)

def copy_file(source_filename, destination_filename):
    try:
        with open(source_filename, 'r') as source_file:
            content = source_file.read()
        with open(destination_filename, 'w') as destination_file:
            destination_file.write(content)
        print(f"Successfully copied '{source_filename}' to '{destination_filename}'.")
    except FileNotFoundError:
        print(f"Error: Source file '{source_filename}' not found.")
    except Exception as e:
        print(f"An error occurred: {e}")
# Example usage:
source_file = "sample.txt"
destination_file = "copied_sample.txt"
copy_file(source_file, destination_file)Code language: Python (python)

# Solution:
def copy_binary_file(source_filename, destination_filename):
    try:
        with open(source_filename, 'rb') as source_file:
            binary_content = source_file.read()
        with open(destination_filename, 'wb') as destination_file:
            destination_file.write(binary_content)
        print(f"Successfully copied binary file '{source_filename}' to '{destination_filename}'.")
    except FileNotFoundError:
        print(f"Error: Source binary file '{source_filename}' not found.")
    except Exception as e:
        print(f"An error occurred: {e}")
# Example usage:
source_binary_file = "input.bin" # Make sure this binary file exists
destination_binary_file = "output.bin"
copy_binary_file(source_binary_file, destination_binary_file)Code language: Python (python)

import os
def check_file_exists(filename):
    return os.path.exists(filename)
# Example usage:
filename = "sample.txt"
exists = check_file_exists(filename)
print(f"Does '{filename}' exist? {exists}")Code language: Python (python)

import os
def get_file_size(filename):
    try:
        size_in_bytes = os.path.getsize(filename)
        return size_in_bytes
    except FileNotFoundError:
        return f"Error: '{filename}' not found."
# Example usage:
filename = "sample.txt"
size = get_file_size(filename)
print(f"The size of '{filename}' is: {size} bytes.")Code language: Python (python)

import os
def rename_file(old_filename, new_filename):
    if not os.path.exists(old_filename):
        return f"Error: File '{old_filename}' not found."
    try:
        os.rename(old_filename, new_filename)
        return f"Successfully renamed '{old_filename}' to '{new_filename}'."
    except Exception as e:
        return f"An error occurred while renaming: {e}"
# Example usage:
old_name = "old_file.txt"
new_name = "new_file.txt"Code language: Python (python)

import os
def delete_file(filename):
    if not os.path.exists(filename):
        return f"Error: File '{filename}' not found."
    try:
        os.remove(filename)
        return f"Successfully deleted '{filename}'."
    except Exception as e:
        return f"An error occurred while deleting: {e}"
# Example usage:
file_to_delete = "temp_file.txt"
# Create a dummy file to test deletion
with open(file_to_delete, 'w') as f:
    f.write("This file will be deleted.")
result = delete_file(file_to_delete)
print(result)Code language: Python (python)

def replace_in_file(source_filename, destination_filename, old_word, new_word):
    try:
        with open(source_filename, 'r') as source_file:
            content = source_file.read()
        modified_content = content.replace(old_word, new_word)
        with open(destination_filename, 'w') as destination_file:
            destination_file.write(modified_content)
        return f"Successfully replaced '{old_word}' with '{new_word}' in '{source_filename}' and saved to '{destination_filename}'."
    except FileNotFoundError:
        return f"Error: Source file '{source_filename}' not found."
    except Exception as e:
        return f"An error occurred: {e}"
# Example usage:
source_file = "sample.txt"
destination_file = "replaced_file.txt"
word_to_replace = "old"
replacement_word = "new"
# Create a dummy file to test replacement
with open(source_file, 'w') as f:
    f.write("This is an old file with some old content.")
result = replace_in_file(source_file, destination_file, word_to_replace, replacement_word)
print(result)Code language: Python (python)