Liens

Code

using System;

namespace MonNS
{
    class MaClasse
    {
        public static void Main(string[] args)
        {
            Console.WriteLine("");
        }
    }
}

Read input

ConsoleKeyInfo keyInfo = Console.ReadKey(true);
if (keyInfo.Key == ConsoleKey.Escape) { }

Masquer la saisie d'un mot de passe

public static string ReadPassword()
{
    string password = "";
    ConsoleKeyInfo info = Console.ReadKey(true);
    while (info.Key != ConsoleKey.Enter)
    {
        if (info.Key != ConsoleKey.Backspace)
        {
            Console.Write("*");
            password += info.KeyChar;
        }
        else if (info.Key == ConsoleKey.Backspace)
        {
            if (!string.IsNullOrEmpty(password))
            {
                // remove one character from the list of password characters
                password = password.Substring(0, password.Length - 1);

                // get the location of the cursor
                int pos = Console.CursorLeft;

                // move the cursor to the left by one character
                Console.SetCursorPosition(pos - 1, Console.CursorTop);

                // replace it with space
                Console.Write(" ");

                // move the cursor to the left by one character again
                Console.SetCursorPosition(pos - 1, Console.CursorTop);
            }
        }

        info = Console.ReadKey(true);
    }

    // add a new line because user pressed enter at the end of their password
    Console.WriteLine();

    return password;
}

Masquer la fenêtre de la Console

[DllImport("kernel32.dll")]
private static extern IntPtr GetConsoleWindow();

[DllImport("user32.dll")]
private static extern bool ShowWindow(IntPtr hWnd, int nCmdShow);

private const int SW_HIDE = 0;
private const int SW_SHOW = 5;

var handle = GetConsoleWindow();
ShowWindow(handle, SW_HIDE);

Couleurs

Console.BackgroundColor = ConsoleColor.DarkRed;
Console.ForegroundColor = ConsoleColor.Green;
Console.WriteLine("...");
Console.ResetColor();

Dependency injection

dotnet add package Microsoft.Extensions.Hosting

Program.cs

var appBuilder = Host.CreateApplicationBuilder(args);
appBuilder.Services.AddSingleton<MyService>();
var host = appBuilder.Build();

var myService = host.Services.GetService<MyService>() ?? throw new NullReferenceException("MyService service");

Logging in .Net Core Console Apps

Serilog

dotnet add package Microsoft.Extensions.Logging.Console

Program.cs

var appBuilder =  Host.CreateApplicationBuilder(args);
appBuilder.Logging
    .ClearProviders()
    .AddConsole();
var host = hostBuilder.Build();

var logger = host.Services.GetService<ILoggerFactory>()?.CreateLogger<Program>() ?? throw new NullReferenceException("ILoggerFactory service");
logger.LogDebug("Starting application");

MyService.cs

private readonly ILogger logger;

public MyService(ILogger logger)
{
    this.logger = logger;
}

Configuration

Program.cs

var appBuilder =  Host.CreateApplicationBuilder(args);
// by default the app load appsettings.json from Directory.GetCurrentDirectory()

// change to load from the directory where the binary is located
var appBuilder = new HostApplicationBuilder(
    new HostApplicationBuilderSettings { ContentRootPath = AppContext.BaseDirectory });

var host = hostBuilder.Build();

MyService.cs

private readonly IConfiguration configuration;

public MyService(IConfiguration configuration)
{
    this.configuration = configuration;
}

var value = configuration.GetValue<string>("key");
var values = Configuration.GetSection("sectionKey").Get<string[]>();

By default the environment is set to Production, so the user secrets storage is not loaded.

Configuration

dotnet add package Microsoft.Extensions.Configuration.Json
dotnet add package Microsoft.Extensions.Configuration.Binder

Program.cs

private static IConfiguration Configuration;

static void Main(string[] args)
{
    var builder = new ConfigurationBuilder()
        .SetBasePath(AppContext.BaseDirectory)  // default value
        .AddJsonFile("appsettings.json");

    Configuration = builder.Build();

    var value1 = Configuration.GetValue<string>("section1");
    var value2 = Configuration.GetValue<int>("section2");
    var values = Configuration.GetSection("section3").Get<string[]>();

MyProject.csproj

<!-- copy the appsettings.json file in the output folder -->
<ItemGroup>
  <None Include="appsettings.json" CopyToOutputDirectory="PreserveNewest" />
</ItemGroup>

Entity Framework Core

Program.cs

// nuget package: Microsoft.Extensions.Hosting

HostApplicationBuilder builder = Host.CreateApplicationBuilder(args);  // allow to use scaffold with a named connection string

var connectionString = builder.Configuration.GetConnectionString("DB1");
var serverVersion = new MariaDbServerVersion(new Version(11, 0, 2));

builder.Services.AddDbContext<DB1Context>(
    dbContextOptions => dbContextOptions
        .UseMySql(connectionString, serverVersion)
        // TODO The following three options help with debugging, but should be changed or removed for production.
        .LogTo(Console.WriteLine, LogLevel.Information)
        .EnableSensitiveDataLogging()
        .EnableDetailedErrors());

builder.Services.AddTransient<ItemRepository>();

using IHost host = builder.Build();

var itemRepository = host.Services.GetService<ItemRepository>();
if (itemRepository is not null)
{
    await itemRepository.GetAllItemsAsync();
}

//await host.RunAsync();