Console App Task 03: Create .log file and write log in C#

Console App Task 03: Create .log file and write log in C# ? 

Here’s a C# console application that creates a .log file and writes logs in the format:

📌 Format: yyyy-MM-dd HH:mm:ss | message

📌 Log File Path: {ApplicationPath}\Output\Log\app.log

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📌 Full Code: Create & Write to a Log File

using System;
using System.IO;

class Program
{
    static void Main()
    {
        // Get application running path and log directory
        string appPath = AppDomain.CurrentDomain.BaseDirectory;
        string logDirectory = Path.Combine(appPath, "Output", "Log");

        // Ensure log directory exists
        Directory.CreateDirectory(logDirectory);

        // Define log file path
        string logFilePath = Path.Combine(logDirectory, "app.log");

        // Example log messages
        WriteLog(logFilePath, "Application started.");
        WriteLog(logFilePath, "Processing data...");
        WriteLog(logFilePath, "Application finished successfully.");

        Console.WriteLine($"Logs written to: {logFilePath}");
    }

    /// <summary>
    /// Writes a log entry to the log file with DateTime | Message format.
    /// </summary>
    static void WriteLog(string filePath, string message)
    {
        string logEntry = $"{DateTime.Now:yyyy-MM-dd HH:mm:ss} | {message}";

        // Append log entry to file
        File.AppendAllText(filePath, logEntry + Environment.NewLine);
    }
}

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📌 Explanation

1. Gets Application Running Path → AppDomain.CurrentDomain.BaseDirectory
2. Creates Output\Log Directory → Ensures log directory exists.
3. Defines Log File Path → app.log
4. Writes Log Messages in DateTime | Message Format
   • Example: 2024-02-08 14:30:10 | Application started.
5. Uses File.AppendAllText() → Appends logs without overwriting the file.

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📌 Example Log File (app.log)

2024-02-08 14:30:10 | Application started.
2024-02-08 14:30:11 | Processing data...
2024-02-08 14:30:12 | Application finished successfully.

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