.NET Разработчик. Страница 16

var instance = new MyAsyncClass();
await instance.InitAsync();

class AsyncClass
{
  private AsyncClass()
  {
  }
  
  private async Task<AsyncClass> InitAsync()
  {
    await Task.Delay(TimeSpan.FromSeconds(1));
    return this;
  }
  
  public static Task<AsyncClass> CreateAsync()
  {
    var result = new AsyncClass();
    return result.InitAsync();
  }
}

var instance = await AsyncClass.CreateAsync();

class AsyncClass
{
  public AsyncClass()
  {
    InitAsync();
  }
  // ПЛОХОЙ КОД!!
  private async void InitAsync()
  {
    await Task.Delay(TimeSpan.FromSeconds(1));
  }
}

public IActionResult Index()
{
  var base = $"{Request.Scheme}://{Request.Host}:{Request.Host.Port ?? 80}";
  return View();
}

public static class HttpRequestExtensions
{
  public static string? BaseUrl(
   this HttpRequest req)
  {
    if (req == null) return null;
    var uriBuilder = new UriBuilder(
     req.Scheme, 
     req.Host.Host,
     req.Host.Port ?? -1);
    
    if (uriBuilder.Uri.IsDefaultPort)
      uriBuilder.Port = -1;
       
    return uriBuilder.Uri.AbsoluteUri;
  }
}

Request.BaseUrl();

var builder = WebApplication.CreateBuilder(args);
builder.Services.AddHttpContextAccessor();
// ...
var app = builder.Build();
// ...

{
  private readonly IHttpContextAccessor hCA;
  public IndexModel(IHttpContextAccessor hCA)
  {
    this.hCA = hCA;
  }

  public void OnGet()
  {
    var baseUrl = 
     hCA.HttpContext?.Request.BaseUrl();
    // ...
  }
}

<TrimMode>partial</TrimMode>

<TrimMode>full</TrimMode>

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net6.0-windows10.0.17763.0</TargetFramework>
  </PropertyGroup>
</Project>

using Windows.Security.Credentials.UI;
async Task<bool> ConsentAsync(string reason)
{
  var availability = await
   UserConsentVerifier.CheckAvailabilityAsync();
  
  if (availability ==
    UserConsentVerifierAvailability.Available)
  {
    var result = await
     UserConsentVerifier
      .RequestVerificationAsync(reason);
    
    return result ==
     UserConsentVerificationResult.Verified;
  }

  return false;
}

if (await ConsentAsync("Confirm your identity"))
  Console.WriteLine("Cofirmed");
else
  Console.WriteLine("Not confirmed");

interface ICountBytes
{
  Task<int> CountBytesAsync(
   HttpClient hc, string url);
}

class Counter : ICountBytes
{
  public async Task<int>
   CountBytesAsync(HttpClient hc, string url)
  {
    var b = await hc.GetByteArrayAsync(url);
    return b.Length;
  }
}

async Task UseCounter(
  HttpClient hc,
  ICountBytes svc)
{
  var res = await svc.CountBytesAsync(
   hc,
   "http://www.google.com");
  
  Console.WriteLine(res);
}

class CounterStub : ICountBytes
{
  public Task<int> CountBytesAsync(
   HttpClient hc, string url)
  {
    return Task.FromResult(13);
  }
}

class async {
}

Regex.IsMatch("०१२३४५६७८९", "[0-9]{10}"); 

Regex.IsMatch("०१२३४५६७८९", "\\d{10}");

Regex.IsMatch("०१२३४५६७८९", "\\d{10}", RegexOptions.ECMAScript);

var regex1 = new Regex("^[a-zA-Z]+$");
var regex2 = new Regex("^[a-z]+$", 
  RegexOptions.IgnoreCase | 
  RegexOptions.CultureInvariant);

regex1.IsMatch("Test"); // True
regex2.IsMatch("Test"); // True

regex1.IsMatch("K"); // False
regex2.IsMatch("K"); // True

public class Person
{
  public long Id { get; set; }
  public string Name { get; set; }
  public int Age { get; set; }
}

var personsDeleted = context.Persons
  .Where(p => p.Name.Contains("L"))
  .ExecuteDelete();

DELETE FROM [p]
FROM [Persons] AS [p]
WHERE [p].[Name] LIKE N'%L%'

var personsUpdated =
  context.Persons
    .Where(p => p.PersonId <= 1_000)
    .ExecuteUpdate(
      p => p.SetProperty(
        x => x.Name,
        x => "New" + x.Name)
    );
}

UPDATE [p]
 SET [p].[Name] = N'New' + [p].[Name]
FROM [Persons] AS [p]
WHERE [p].[Id] <= CAST(1000 AS bigint)

….ExecuteUpdate(p =>
   p.SetProperty(x => x.Name, x => "…")
    .SetProperty(x => x.Age, x => 42)
  );
}