public interface IHaveTrackingState
{
    TrackingState TrackingState { get; set; }
    //ICollection<string> ModifiedProperties { get; set; }
}

public enum TrackingState
{
    Unchanged = 0,
    Added = 1,
    Modified = 2,
    Deleted = 3
}

Mapper.Initialize(expression =>
{
    expression.CreateMap<MasterModel, Master>(MemberList.None).ReverseMap();
    expression.CreateMap<DetailModel, Detail>(MemberList.None).ReverseMap();
    expression.CreateMap<DetailOfDetailModel, DetailOfDetail>(MemberList.None).ReverseMap();
});

البته بهتر است این تنظیمات در درون Profile‌های مرتبط با AutoMapper کپسوله شوند و در زمان مورد نیاز نیز برای انجام نگاشت‌ها، واسط IMapper تزریق شده و استفاده شود.

using (var context = new ProjectDbContext())
{
    Console.WriteLine("################ Create Master and Details and DetailsOfDetail ##################");
    Print(masterModel);

    var masterEntity = Mapper.Map<Master>(masterModel);

    context.ChangeTracker.TrackGraph(
        masterEntity,
        n =>
        {
            var entity = (IHaveTrackingState) n.Entry.Entity;
            n.Entry.State = entity.TrackingState.ToEntityState();
        });

    context.SaveChanges();
}

در تکه کد بالا، پس از انجام عملیات نگاشت، توسط متد TrackGraph به صورت صریح، وضعیت موجودیت‌ها مشخص شده است؛ این کار با تغییر State ارسالی توسط کلاینت به State قابل فهم توسط EF انجام شده‌است. برای این منظور دو متد الحاقی زیر را می‌توان در نظر گرفت:

//GetForEditAsync
var masterModel = context.Masters
    .ProjectTo<MasterModel>()
    .AsNoTracking().Single(a => a.Id == 1);

//Client
var detail1 = masterModel.Details.First();
detail1.Title = "Details-EditedTitle";
detail1.TrackingState = TrackingState.Modified;

foreach (var detail in detail1.Details)
{
    detail.TrackingState = TrackingState.Deleted;
    //detail.Title = "DetailOfDetails-EditedTitle";
}

برای بحث اعتبارسنجی هم می‌توان به شکل زیر عمل کرد:

public class MasterValidator : AbstractValidator<MasterModel>
{
    public MasterValidator()
    {
        RuleFor(a => a.Title).NotEmpty();
        RuleForEach(a => a.Details).SetValidator(new DetailValidator());
    }
}

public class DetailValidator : AbstractValidator<DetailModel>
{
    public DetailValidator()
    {
        RuleFor(a => a.Title).NotEmpty();
        RuleForEach(a => a.Details).SetValidator(new DetailOfDetailValidator());
    }
}

public class DetailOfDetailValidator : AbstractValidator<DetailOfDetailModel>
{
    public DetailOfDetailValidator()
    {
        RuleFor(a => a.Title).NotEmpty();
    }
}

با استفاده از متد RuleForEach و SetValidator موجود در کتابخانه FluentValidation، امکان مشخص کردن اعتبارسنج برای Detail موجود در شیء Master را خواهیم داشت.

همچنین با توجه به این که برای عملیات Create و Edit از یک مدل (DTO) استفاده خواهیم کرد، شاید لازم باشد اعتبارسنجی خاصی را فقط در زمان ویرایش لازم داشته باشیم، که در این صورت می‌توان از امکانات RuleSet استفاده کنید. در مطلب «طراحی و پیاده سازی ServiceLayer به همراه خودکارسازی Business Validationها» با استفاده ValidateWithRuleAttribute امکان مشخص کردن RuleSet مورد نظر برای اعتبارسنجی ورودی متد سرویس نیز در نظر گرفته شده است.

منابع تکمیلی

• ChangeTracker.TrackGraph() in Entity Framework Core 
• Disconnected entities 
• https://msdn.microsoft.com/magazine/mt694083 
• https://msdn.microsoft.com/magazine/mt767693
  
• https://blog.tonysneed.com/2017/10/01/trackable-entities-for-ef-core/ 
  
• Tracking Individually Modified Properties 
  

 public class Person:BaseEntity
    {
        public int PersonId { get; set; }        
        [StringLength(100)]
        public string Title { get; set; }
        public PersonType PersonType { get; set; }
        public virtual ICollection<PrivacyPolicy> PrivacyPolicies { get; set; }


        public override string ToString()
        {
            return Title;
        }
    }

 public interface CopyFileListener
    {
        void PublishProgress(long fileSize,long copiedSize);
    }

 textView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                
            }
        });

public class MemoryWare {

    public interface CopyFileListener
    {
        void PublishProgress(long fileSize,long copiedSize);
    }
....
}

SetOnClickListener

 editText.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {

            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {

            }

            @Override
            public void afterTextChanged(Editable s) {

            }
        });

  @Override
    public View getView(int position, View rowView, ViewGroup parent) {

        ViewHolder viewHolder=null;
        if(rowView==null)
        {
            // 1. Create inflater
            LayoutInflater inflater = (LayoutInflater) context
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

            // 2. Get rowView from inflater
            rowView = inflater.inflate(R.layout.row_bank_group_list, parent, false);
            viewHolder=new ViewHolder();
            viewHolder.txtGroupName=(TextView) rowView.findViewById(R.id.text_groupName);
            rowView.setTag(viewHolder);
        }
        else
        {
            viewHolder=(ViewHolder)rowView.getTag();
        }
        viewHolder.txtGroupName.setText(getItem(position).getName());
        viewHolder.txtGroupName.setTypeface(new FontSystem().get_General_Font(context));
        viewHolder.txtGroupName.setTextColor(context.getResources().getColor(R.color.black));

        return rowView;
    }

File file=new File(sdcardPath,fileName);

if(file.CanWrite())
{
  .....
}

File file=new File(sdcardPath);

if(file.CanWrite())
{
file=new File(sdcardPath,filePath);
  .....
}

Environment.getExternalStorageDirectory()

/Data/Data

/Data/Data/Info.Dotnettips.MyApp

    /**
     * it will returns sd path for you
     *  <p>
     *  <b>Required Permission: </b>android.permission.READ_EXTERNAL_STORAGE<br/>
     * </p>
     * @return
     */
    public  List<String> GetExternalMounts() {
        final List<String> out = new ArrayList<>();
        String reg = "(?i).*vold.*(vfat|ntfs|exfat|fat32|ext3|ext4).*rw.*";
        String s = "";
        try {
            final Process process = new ProcessBuilder().command("mount")
                    .redirectErrorStream(true).start();
            process.waitFor();
            final InputStream is = process.getInputStream();
            final byte[] buffer = new byte[1024];
            while (is.read(buffer) != -1) {
                s = s + new String(buffer);
            }
            is.close();
        } catch (final Exception e) {
            e.printStackTrace();
        }

        // parse output
        final String[] lines = s.split("\n");
        for (String line : lines) {
            if (!line.toLowerCase(Locale.US).contains("asec")) {
                if (line.matches(reg)) {
                    String[] parts = line.split(" ");
                    for (String part : parts) {
                        if (part.startsWith("/"))
                            if (!part.toLowerCase(Locale.US).contains("vold"))
                                if(new File(part).canWrite())
                                    out.add(part);
                    }
                }
            }
        }
        return out;
    }

notesIntent.putExtra("PartyId", PartyId);
startActivity(notesIntent);

PartyId=getIntent().getLongExtra("PartyId",0);

i.putExtra(FilePickerActivity.EXTRA_ALLOW_MULTIPLE, false);
i.putExtra(FilePickerActivity.EXTRA_ALLOW_CREATE_DIR, false);
i.putExtra(FilePickerActivity.EXTRA_MODE, FilePickerActivity.MODE_FILE);

• برای ثابت‌ها از حروف بزرگ و _ استفاده کنید.
• برای متغیرهای خصوصی از حرف m در ابتدای نام متغیر استفاده کنید.
• برای متغیرهای استاتیک از حرف s در ابتدای نام متغیر استفاده کنید.

public class MyClass {
    public static final int SOME_CONSTANT = 42;
    public int publicField;
    private static MyClass sSingleton;
    int mPackagePrivate;
    private int mPrivate;
    protected int mProtected;
}

1. نام پکیج‌های ارائه شده توسط گوگل
2. نام پکیج‌های ثالث
3. نام پکیج‌های موجود در java و javax
4. پکیج‌های موجود در پکیج اصلی
   

public, protected, private,abstract, static, transient, volatile, synchronized, final, native.

Settings>Editor>Code Style>Arrangement

Settings>Editor>Completion>Case-sensitive Completion>None

// Add custom user claims here
userIdentity.AddClaim(new Claim("key1", "value1"));

public static string GetClaimValue(this IPrincipal currentPrincipal, string key)
{
     var identity = currentPrincipal.Identity as ClaimsIdentity;
     if (identity == null)
          return null;

     var claim = identity.Claims.FirstOrDefault(c => c.Type == key);
     return claim?.Value;
}

using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;
using System.Collections.Generic;
using System.Linq;


[MemoryDiagnoser(displayGenColumns: false)]
public partial class Program
{
  static void Main(string[] args) =>
    BenchmarkSwitcher.FromAssembly(typeof(Program).Assembly).Run(args);

  [Params (10, 10000)]
  public int Size { get; set; }
  private IEnumerable<int> items;

  [GlobalSetup]
  public void Setup()
  {
    items = Enumerable.Range(1, Size).ToArray();
  }  

  [Benchmark]
  public int Min() => items.Min();

  [Benchmark]
  public int Max() => items.Max();

  [Benchmark]
  public double Average() => items.Average();

  [Benchmark]
  public int Sum() => items.Sum();
}

public static int Min(this IEnumerable<int> source)
{
  if (source == null)
  {
    ThrowHelper.ThrowArgumentNullException(ExceptionArgument.source);
  }

  int value;
  using (IEnumerator<int> e = source.GetEnumerator())
  {
    if (!e.MoveNext())
    {
      ThrowHelper.ThrowNoElementsException();
    }

    value = e.Current;
    while (e.MoveNext())
    {
      int x = e.Current;
      if (x < value)
      {
        value = x;
      }
    }
  }
  return value;
}

public static int Min(this IEnumerable<int> source) => MinInteger(source);

private static T MinInteger<T>(this IEnumerable<T> source)
  where T : struct, IBinaryInteger<T>
{
  T value;

  if (source.TryGetSpan(out ReadOnlySpan<T> span))
  {
    if (Vector.IsHardwareAccelerated && 
        span.Length >= Vector<T>.Count * 2)
    {
      .... // Optimized implementation
      return ....;
    }
  }
  .... //Implementation as in .NET 6
}

if (Vector.IsHardwareAccelerated && span.Length >= Vector<T>.Count * 2)

private static T MinInteger<T>(this IEnumerable<T> source)
where T : struct, IBinaryInteger<T>
{
  .... 
  if (Vector.IsHardwareAccelerated && span.Length >= Vector<T>.Count * 2)
  {
    var mins = new Vector<T>(span);
    index = Vector<T>.Count;
    do
    {
      mins = Vector.Min(mins, new Vector<T>(span.Slice(index)));
      index += Vector<T>.Count;
    }
    while (index + Vector<T>.Count <= span.Length);

    value = mins[0];
    for (int i = 1; i < Vector<T>.Count; i++)
    {  
      if (mins[i] < value)
      {
        value = mins[i];
      }
    }
  ....
}

        public static int ToInt(this string data)
        {
            if (string.IsNullOrWhiteSpace(data)) return 0;
            int result;
            return int.TryParse(data, out result) ? result : 0;
        }

FormsAuthentication.SetAuthCookie(user.Id.ToString(CultureInfo.InvariantCulture), ...
// ...
FormsAuthentication.RedirectFromLoginPage(user.Id.ToString(CultureInfo.InvariantCulture), ...

namespace DbConfig.Web.DomainClasses
{
    public class ConfigurationValue
    {
        public int Id { get; set; }
        public string Key { get; set; }
        public string Value { get; set; }
    }
}

    public class MyAppContext : DbContext, IUnitOfWork
    {
        public MyAppContext(DbContextOptions options) : base(options)
        { }

        public virtual DbSet<ConfigurationValue> Configurations { set; get; }

        protected override void OnModelCreating(ModelBuilder builder)
        {
            // it should be placed here, otherwise it will rewrite the following settings!
            base.OnModelCreating(builder);

            // Custom application mappings
            builder.Entity<ConfigurationValue>(entity =>
            {
                entity.Property(e => e.Key).HasMaxLength(450).IsRequired();
                entity.HasIndex(e => e.Key).IsUnique();
                entity.Property(e => e.Value).IsRequired();
                entity.HasData(new ConfigurationValue
                {
                    Id = 1,
                    Key = "key-1",
                    Value = "value_from_ef_1"
                });
                entity.HasData(new ConfigurationValue
                {
                    Id = 2,
                    Key = "key-2",
                    Value = "value_from_ef_2"
                });
            });
        }

    public class EFConfigurationSource : IConfigurationSource
    {
        private readonly IServiceProvider _serviceProvider;

        public EFConfigurationSource(IServiceProvider serviceProvider)
        {
            _serviceProvider = serviceProvider;
        }

        public IConfigurationProvider Build(IConfigurationBuilder builder)
        {
            return new EFConfigurationProvider(_serviceProvider);
        }
    }

    public class EFConfigurationProvider : ConfigurationProvider
    {
        private readonly IServiceProvider _serviceProvider;

        public EFConfigurationProvider(IServiceProvider serviceProvider)
        {
            _serviceProvider = serviceProvider;
            ensureDatabaseIsCreated();
        }

        public override void Load()
        {
            using (var scope = _serviceProvider.CreateScope())
            {
                var uow = scope.ServiceProvider.GetRequiredService<IUnitOfWork>();
                this.Data?.Clear();
                this.Data = uow.Set<ConfigurationValue>()
                               .AsNoTracking()
                               .ToList()
                               .ToDictionary(c => c.Key, c => c.Value);
            }
        }

        private void ensureDatabaseIsCreated()
        {
            using (var scope = _serviceProvider.CreateScope())
            {
                var uow = scope.ServiceProvider.GetRequiredService<IUnitOfWork>();
                uow.Migrate();
            }
        }
    }

    public static class EFExtensions
    {
        public static IConfigurationBuilder AddEFConfig(this IConfigurationBuilder builder,
            IServiceProvider serviceProvider)
        {
            return builder.Add(new EFConfigurationSource(serviceProvider));
        }
    }

namespace DbConfig.Web
{
    public class Startup
    {
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddScoped<IUnitOfWork, MyAppContext>();
            services.AddScoped<IConfigurationValuesService, ConfigurationValuesService>();

            var connectionString = Configuration.GetConnectionString("SqlServerConnection")
                     .Replace("|DataDirectory|", Path.Combine(Directory.GetCurrentDirectory(), "wwwroot", "app_data"));
            services.AddDbContext<MyAppContext>(options =>
                    {
                        options.UseSqlServer(
                            connectionString,
                            dbOptions =>
                                {
                                    var minutes = (int)TimeSpan.FromMinutes(3).TotalSeconds;
                                    dbOptions.CommandTimeout(minutes);
                                    dbOptions.EnableRetryOnFailure();
                                });
                    });

            var serviceProvider = services.BuildServiceProvider();
            var configuration = new ConfigurationBuilder()
                                       .AddConfiguration(Configuration) // Adds all of the existing configurations
                                       .AddEFConfig(serviceProvider)
                                       .Build();
            services.AddSingleton<IConfigurationRoot>(sp => configuration); // Replace
            services.AddSingleton<IConfiguration>(sp => configuration); // Replace

namespace DbConfig.Web.Controllers
{
    public class HomeController : Controller
    {
        private readonly IConfiguration _configuration;

        public HomeController(IConfiguration configuration)
        {
            _configuration = configuration;
        }

        public IActionResult Index()
        {
            return Json(
                new
                {
                    key1 = _configuration["key-1"],
                    key2 = _configuration["key-2"]
                });
        }

    public class ConfigurationValuesService : IConfigurationValuesService
    {
        private readonly IConfiguration _configuration;

        public ConfigurationValuesService(IConfiguration configuration)
        {
            _configuration = configuration;
        }

        private void reloadEFConfigurationProvider()
        {
            ((IConfigurationRoot)_configuration).Reload();
        }

var mockIdentityVerifier = new Mock<IIdentityVerifier>(MockBehavior.Strict);

Test method Loans.Tests.LoanApplicationProcessorShould.Accept threw exception:
Moq.MockException: IIdentityVerifier.Initialize() invocation failed with mock behavior Strict.
All invocations on the mock must have a corresponding setup.

mockIdentityVerifier.Setup(x => x.Initialize());

try
{
    _creditScorer.CalculateScore(application.Applicant.Name, application.Applicant.Address);
}
catch
{
    return application.IsAccepted;
}
 

mockCreditScorer.Setup(x =>
                    x.CalculateScore(It.IsAny<string>(), It.IsAny<string>()))
                .Throws(new InvalidOperationException("Test Exception"));

Assert.IsFalse(application.IsAccepted);

using System;

namespace Loans.Models
{
    public class CreditScoreResultArgs : EventArgs
    {
        public int Score { get; set; }
    }
}

public interface ICreditScorer
{
   event EventHandler<CreditScoreResultArgs> ResultAvailable;

mockCreditScorer.Raise(x => x.ResultAvailable += null, new CreditScoreResultArgs());

mockCreditScorer.Setup(x =>
                x.CalculateScore(It.IsAny<string>(), It.IsAny<string>()))
                .Raises(x => x.ResultAvailable += null, new CreditScoreResultArgs());

namespace Loans.Tests
{
    [TestClass]
    public class LoanApplicationProcessorShould
    {        
        [TestMethod]
        public void AcceptUsingPartialMock()
        {
            var product = new LoanProduct {Id = 99, ProductName = "Loan", InterestRate = 5.25m};
            var amount = new LoanAmount {CurrencyCode = "Rial", Principal = 2_000_000_0};
            var applicant =
                new Applicant {Id = 1, Name = "User 1", Age = 25, Address = "This place", Salary = 1_500_000_0};
            var application = new LoanApplication {Id = 42, Product = product, Amount = amount, Applicant = applicant};

            var mockIdentityVerifier = new Mock<IdentityVerifierServiceGateway>();

            mockIdentityVerifier.Setup(x => x.CallService(applicant.Name, applicant.Age, applicant.Address))
                .Returns(true);

            var mockCreditScorer = new Mock<ICreditScorer>();
            mockCreditScorer.Setup(x => x.ScoreResult.ScoreValue.Score).Returns(110_000);

            var sut = new LoanApplicationProcessor(mockIdentityVerifier.Object, mockCreditScorer.Object);
            sut.Process(application);

            Assert.IsTrue(application.IsAccepted);
        }
    }
}

public virtual bool CallService(string applicantName, int applicantAge, string applicantAddress)

public bool Validate(string applicantName, int applicantAge, string applicantAddress)
{
    Connect();
    var isValidIdentity = CallService(applicantName, applicantAge, applicantAddress);
    LastCheckTime = DateTime.Now;
    Disconnect();

    return isValidIdentity;
}

public bool Validate(string applicantName, int applicantAge, string applicantAddress)
{
    Connect();
    var isValidIdentity = CallService(applicantName, applicantAge, applicantAddress);
    LastCheckTime = GetCurrentTime();
    Disconnect();

    return isValidIdentity;
}

public virtual DateTime GetCurrentTime()
{
    return DateTime.Now;
}

var expectedTime = new DateTime(2000, 1, 1);
mockIdentityVerifier.Setup(x => x.GetCurrentTime())
    .Returns(expectedTime);
// ...
Assert.AreEqual(expectedTime, mockIdentityVerifier.Object.LastCheckTime);

mockIdentityVerifier.Protected().Setup<bool>(
        "CallService",applicant.Name, applicant.Age, applicant.Address)
    .Returns(true);

var expectedTime = new DateTime(2000, 1, 1);
mockIdentityVerifier.Protected().Setup<DateTime>("GetCurrentTime")
    .Returns(expectedTime);

interface IIdentityVerifierServiceGatewayProtectedMembers
{
   DateTime GetCurrentTime();
   bool CallService(string applicantName, int applicantAge, string applicantAddress);
}

mockIdentityVerifier.Protected()
    .As<IIdentityVerifierServiceGatewayProtectedMembers>()
    .Setup(x => x.CallService(It.IsAny<string>(),
        It.IsAny<int>(),
        It.IsAny<string>()))
    .Returns(true);

var expectedTime = new DateTime(2000, 1, 1);
mockIdentityVerifier.Protected()
    .As<IIdentityVerifierServiceGatewayProtectedMembers>()
    .Setup(x => x.GetCurrentTime())
    .Returns(expectedTime);

using System;

namespace Loans.Services.Contracts
{
    public interface INowProvider
    {
        DateTime GetNow();
    }
}

    public class IdentityVerifierServiceGateway : IIdentityVerifier
    {
        private readonly INowProvider _nowProvider;
        
        public DateTime LastCheckTime { get; private set; }

        public IdentityVerifierServiceGateway(INowProvider nowProvider)
        {
            _nowProvider = nowProvider;
        }

        public bool Validate(string applicantName, int applicantAge, string applicantAddress)
        {
            Connect();
            var isValidIdentity = CallService(applicantName, applicantAge, applicantAddress);
            LastCheckTime = _nowProvider.GetNow();
            // ...

var mockNowProvider = new Mock<INowProvider>();
mockNowProvider.Setup(x => x.GetNow()).Returns(expectedTime);

var mockIdentityVerifier =  new Mock<IdentityVerifierServiceGateway>(mockNowProvider.Object);