How to Handle File Operations in C#

Introduction

In this article, we will explore a C# program that performs various file operations, such as reading and writing to a text file. The program also demonstrates exception handling and object-oriented programming concepts. Let's dive into the code and understand its functionality.

Program Structure

The program consists of a single class called Program. This class contains the Main method, which serves as the entry point for the program. Additionally, it includes several helper methods for file operations.

Reading File Contents

The program starts by defining a file path to a text file using the filePath variable. It then initializes two variables, characterCount and wordCount, to keep track of the number of characters and words in the file, respectively.

Next, the program attempts to read the file using a StreamReader object wrapped in a using statement. The StreamReader allows us to read the file line by line. Inside a while loop, the program reads each line and updates the character count by adding the length of the line. It also updates the word count by splitting the line into words using the Split method and counting the non-empty entries.

After reading the entire file, the program displays the total number of characters and words on the console using the Console.WriteLine method.

using System;
using System.IO;

class Program
{
    static void Main()
    {
        string filePath = "sample.txt";
        int characterCount = 0, wordCount = 0;

        try
        {
            using (StreamReader reader = new StreamReader(filePath))
            {
                string line;
                while ((line = reader.ReadLine()) != null)
                {
                    characterCount += line.Length;
                    wordCount += line.Split(' ', StringSplitOptions.RemoveEmptyEntries).Length;
                }
            }
            Console.WriteLine($"Total Characters: {characterCount}");
            Console.WriteLine($"Total Words: {wordCount}");
        }
        catch (FileNotFoundException)
        {
            Console.WriteLine("Error: File not found.");
        }
        catch (Exception ex)
        {
            Console.WriteLine($"An error occurred: {ex.Message}");
        }
    }
}

Exception Handling

To handle potential errors, the program includes a try-catch block. If the file specified by the file path is not found, a FileNotFoundException is thrown. The program catches this exception and displays a user-friendly error message using the Console.WriteLine method.

If any other exception occurs during file reading, it is caught by the generic Exception catch block. The program then displays the error message provided by the exception using the ex.Message property.

Accepting User Input

After reading the file, the program prompts the user to enter author details. It uses the Console.ReadLine method to read the user's input for the name, email, and country. These inputs are stored in the respective variables name, email, and country.

Object-Oriented Programming

The program demonstrates object-oriented programming principles by creating an instance of the Author class. The Author class is defined separately and contains properties for the author's name, email, and country.

Using the user-provided inputs, the program initializes a new Author object and assigns the values to its properties.

Writing to File

The program calls the AddAuthorToFile method, passing the filePath and author objects as arguments. This method appends the author's details to the end of the file using a StreamWriter object wrapped in a using statement. The StreamWriter allows us to write text to a file.

Inside the using block, the program writes the author's name, email, and country to the file using the WriteLine method of the StreamWriter. It also adds an empty line for better readability.

Additional File Operations

• The Program class includes two more helper methods: ReadLineByLine and ReadAllLines. These methods demonstrate different ways to read the contents of a file.
• The ReadLineByLine method reads the file line by line using a StreamReader object and displays each line on the console using the Console.WriteLine method.
• The ReadAllLines method reads all the lines of the file into an array of strings using the File.ReadAllLines method. It then iterates over the array and displays each line on the console.

Conclusion

In this blog, we explored a C# program that performs file operations, exception handling, and object-oriented programming concepts. We learned how to read the contents of a file, handle exceptions, accept user input, create objects, and write to a file. Understanding these concepts is crucial for building robust and interactive applications.

While the above content may be accurate but make sure you read through it and change it as needed before publishing it anywhere.

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