Application console

Liens

• Spectre.Console
• Command Line Parser Library
• Async Main

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();