Write a Python Program to Count the Number of Lines in a Text File

1. Open the File: We’ll start by opening the text file in Python using the `open()` function.
2. Read the Lines: Once the file is open, we’ll read its contents line by line using a loop.
3. Counting Lines: For each line (non-empty lines) we read, we’ll increment a counter to keep track of the number of lines.
4. Display the Count: Finally, we’ll display the total count of lines in the text file.

def count_lines(file_name):
    try:
        with open(file_name, 'r') as file:
            line_count = 0

            content = file.read()
            content = content.split("n")

            for line in content:
                # Checking if the line is empty
                if line:
                    line_count += 1
            return line_count
    except FileNotFoundError:
        print("File not found.")
        return -1  # Return -1 to indicate an error

if __name__ == "__main__":
    file_name = input("Enter the name of the text file: ")
    lines = count_lines(file_name)
    
    if lines >= 0:
        print(f"The file '{file_name}' contains {lines} lines.")

1. The `count_lines()` function takes a filename as an argument.
2. We use a `try` block to catch any potential `FileNotFoundError` that might occur if the specified file does not exist.
3. Within the `with open()` block, we use a `for` loop to iterate through each line in the file. The loop increments the `line_count` for each non-empty line encountered.
4. After the loop completes, the function returns the `line_count`.
5. In the` __main__` block, we take user input for the file name.
6. We call the `count_lines()` function with the provided file name and store the returned value in the `lines` variable.
7. If the value of `lines` is greater than or equal to 0, we display the total number of lines in the file. Otherwise, we display an error message.

1. Save the code in a `.py` file (e.g., `line_counter.py`).
2. Place the text file you want to count lines for in the same directory as the Python script.
3. Open a terminal and navigate to the directory where the script is located.
4. Run the script using the command: `python line_counter.py`.
5. Follow the prompts to enter the name of the text file.
6. The program will display the total number of lines in the specified text file.