public class NestedClass
{
    private int _field2;
    public NestedClass()
    {
        _field2 = 12;
    }
}
 
public class MyClass
{
    private int _field1;
    private NestedClass _nestedClass;
 
    public MyClass()
    {
        _field1 = 1;
        _nestedClass = new NestedClass();
    }
 
    private string GetData()
    {
        return "Test";
    }
}

var myClass = new MyClass();
 
var field1Obj = myClass.GetType().GetField("_field1", BindingFlags.NonPublic | BindingFlags.Instance);
if (field1Obj != null)
{
    Console.WriteLine(Convert.ToInt32(field1Obj.GetValue(myClass)));
}

var getDataMethod = myClass.GetType().GetMethod("GetData", BindingFlags.NonPublic | BindingFlags.Instance);
if (getDataMethod != null)
{
    Console.WriteLine(getDataMethod.Invoke(myClass, null));
}

var nestedClassObj = myClass.GetType().GetField("_nestedClass", BindingFlags.NonPublic | BindingFlags.Instance);
if (nestedClassObj != null)
{
    var nestedClassFieldValue = nestedClassObj.GetValue(myClass);
    var field2Obj = nestedClassFieldValue.GetType()
        .GetField("_field2", BindingFlags.NonPublic | BindingFlags.Instance);
    if (field2Obj != null)
    {
        Console.WriteLine(Convert.ToInt32(field2Obj.GetValue(nestedClassFieldValue)));
    }
}

myClass._field1
myClass._nestedClass._field2
myClass.GetData()

 // Accessing a private field
dynamic myClassProxy = new DynamicProxy(myClass);
dynamic field1 = myClassProxy._field1;
Console.WriteLine((int)field1);
 
// Accessing a nested private field
dynamic field2 = myClassProxy._nestedClass._field2;
Console.WriteLine((int)field2);
 
// Accessing a private method
dynamic data = myClassProxy.GetData();
Console.WriteLine((string)data);

• در متد تحریف شده‌ی OnOpenDocument ، یک قالب PDF ساده را تولید می‌کنیم (مثلا یک مستطیل کوچک خالی).
• سپس در متد OnEndPage ، این قالب را به انتهای تمام صفحات در حال تولید اضافه خواهیم کرد.
• زمانیکه متد OnCloseDocument فراخوانده شد، عدد تعداد کل صفحات را در این قالب که به تمام صفحات اضافه شده، درج خواهیم کرد. به این ترتیب این عدد به صورت خودکار در تمام صفحات نمایش داده خواهد شد.

using System;
using System.IO;
using iTextSharp.text;
using iTextSharp.text.pdf;

namespace iTextSharpTests
{
   public class PdfWriterPageEvents : PdfPageEventHelper
   {
       PdfContentByte _pdfContentByte;
       // عدد نهایی تعداد کل صفحات را در این قالب قرار خواهیم داد
       PdfTemplate _template;
       BaseFont _baseFont;

       public override void OnOpenDocument(PdfWriter writer, Document document)
       {
           _baseFont = BaseFont.CreateFont(BaseFont.HELVETICA, BaseFont.CP1252, BaseFont.NOT_EMBEDDED);
           _pdfContentByte = writer.DirectContent;
           _template = _pdfContentByte.CreateTemplate(50, 50);
       }

       public override void OnEndPage(PdfWriter writer, Document document)
       {
           base.OnEndPage(writer, document);
           String text = writer.PageNumber + "/";
           float len = _baseFont.GetWidthPoint(text, 8);
           Rectangle pageSize = document.PageSize;
           _pdfContentByte.SetRGBColorFill(100, 100, 100);
           _pdfContentByte.BeginText();
           _pdfContentByte.SetFontAndSize(_baseFont, 8);
           _pdfContentByte.SetTextMatrix(pageSize.GetLeft(40), pageSize.GetBottom(30));
           _pdfContentByte.ShowText(text);
           _pdfContentByte.EndText();
           //در پایان هر صفحه یک جای خالی را مخصوص تعداد کل صفحات رزرو خواهیم کرد
           _pdfContentByte.AddTemplate(_template, pageSize.GetLeft(40) + len, pageSize.GetBottom(30));
       }
       public override void OnCloseDocument(PdfWriter writer, Document document)
       {
           base.OnCloseDocument(writer, document);
           _template.BeginText();
           _template.SetFontAndSize(_baseFont, 8);
           _template.SetTextMatrix(0, 0);
           //درج تعداد کل صفحات در تمام قالب‌های اضافه شده
           _template.ShowText((writer.PageNumber - 1).ToString());
           _template.EndText();
       }
   }

   public class AddTotalNoPages
   {
       public static void CreateTestPdf()
       {
           using (var pdfDoc = new Document(PageSize.A4))
           {
               var pdfWriter = PdfWriter.GetInstance(pdfDoc, new FileStream("tpn.pdf", FileMode.Create));
               pdfWriter.PageEvent = new PdfWriterPageEvents();
               pdfDoc.Open();


               pdfDoc.Add(new Phrase("Page1"));
               pdfDoc.NewPage();
               pdfDoc.Add(new Phrase("Page2"));
               pdfDoc.NewPage();
               pdfDoc.Add(new Phrase("Page3"));
           }
       }
   }
}

var x;
var n = 12;
var obj = {};
var fn = function () { };
var a = new Array();

alert(typeof x);        // "undefined"
alert(typeof n);        // "number"
alert(typeof obj);     // "object"
alert(typeof fn);       // "function"
alert(typeof a);        // "object"

result = variable instanceof constructor

var a = new Array();
alert(a instanceof Array); // true
alert(a instanceof Object);   // true
alert(a instanceof Date); // false

var person = {
    name: "Meysam",
    age: 33,
    sayInfo: function () {
        alert(name + ":" + age);
    }
};

for (var i in person) 
    alert(i + " => " + person[i]);

     name => Meysam

    age => 33

    sayInfo => function() {
        alert(name + ":" + age);
    }

alert("name" in person); // true
alert("sayInfo" in person); // true
alert("birth" in person); // false

var person = {
    name: "Meysam",
    age: 33,
    sayInfo: function () {
        alert(name + ":" + age);
    }
};

alert("sayInfo" in person); // true
delete person.sayInfo;
alert("sayInfo" in person); // false

var obj = {};
var a = new Array();
var x = 10;

alert(obj.constructor);
alert(obj.constructor === Object);
alert(typeof obj.constructor);
alert(a.constructor);
alert(x.constructor);

    function Object() { [native code] }
    true
    function
    function Array() { [native code] }
    function Number() { [native code] }

        private static void disposedContext()
        {
            using (var context = new MyContext())
            {
                Debug.WriteLine("Posts count: " + context.BlogPosts.Count());
            }
        }

        private static void nonDisposedContext()
        {
            var context = new MyContext();
            Debug.WriteLine("Posts count: " + context.BlogPosts.Count());
        }

using System.Data;
using System.Data.Common;
using System.Data.Entity.Infrastructure.Interception;

namespace EFNonDisposedContext.Core
{
    public class DatabaseInterceptor : IDbConnectionInterceptor
    {
        public void Closed(DbConnection connection, DbConnectionInterceptionContext interceptionContext)
        {
            Connections.AddOrUpdate(connection, ConnectionStatus.Closed);
        }

        public void Disposed(DbConnection connection, DbConnectionInterceptionContext interceptionContext)
        {
            Connections.AddOrUpdate(connection, ConnectionStatus.Disposed);
        }

        public void Opened(DbConnection connection, DbConnectionInterceptionContext interceptionContext)
        {
            Connections.AddOrUpdate(connection, ConnectionStatus.Opened);
        }
      
        // the rest of the IDbConnectionInterceptor methods ...

    }
}

    public enum ConnectionStatus
    {
        None,
        Opened,
        Closed,
        Disposed
    }

    public class ConnectionInfo
    {
        public string ConnectionId { set; get; }
        public string StackTrace { set; get; }
        public ConnectionStatus Status { set; get; }

        public override string ToString()
        {
            return string.Format("{0}:{1} [{2}]",ConnectionId, Status, StackTrace);
        }
    }

public class Startup 
{ 
    public void ConfigureServices(IServiceCollection services) 
    { 
        // ... 
         
        services.AddTransient<ICustomerService, DefaultCustomerService>(); 
         
        // ... 
    } 
}

public class SupportController 
{ 
    // DefaultCustomerService will be injected here: 
    public SupportController(ICustomerService customerService) 
    { 
        // ... 
    } 
}

namespace Microsoft.Extensions.DependencyInjection
{
    public static class ServiceCollectionServiceExtensions
    {
        public static IServiceCollection AddScoped<TService>(
     this IServiceCollection services) where TService : class;
        public static IServiceCollection AddScoped(
     this IServiceCollection services, Type serviceType, Type implementationType);
        public static IServiceCollection AddScoped(
     this IServiceCollection services, Type serviceType, 
 Func<IServiceProvider, object> implementationFactory);
        public static IServiceCollection AddScoped<TService, TImplementation>(this IServiceCollection services)
        public static IServiceCollection AddScoped(
     this IServiceCollection services, Type serviceType);
        public static IServiceCollection AddScoped<TService>(
     this IServiceCollection services, 
 Func<IServiceProvider, TService> implementationFactory) where TService : class;
        public static IServiceCollection AddScoped<TService, TImplementation>(
     this IServiceCollection services, 
 Func<IServiceProvider, TImplementation> implementationFactory)
// ...
    }
}

namespace CoreIocServices
{
    public interface IParameterizedService
    {
        string GetConstructorParameter();
    }

    public class ParameterizedService : IParameterizedService
    {
        private readonly string _connectionString;

        public ParameterizedService(string connectionString)
        {
            _connectionString = connectionString;
        }

        public string GetConstructorParameter()
        {
            return _connectionString;
        }
    }
}

services.AddTransient<IParameterizedService, ParameterizedService>();

services.AddTransient<IParameterizedService>(serviceProvider =>
{
   return new ParameterizedService("some value ....");
});

services.AddTransient<IParameterizedService>(serviceProvider => new ParameterizedService("some value ...."));

services.AddTransient<IParameterizedService>(serviceProvider =>
{
   var config = serviceProvider.GetRequiredService<ITestService>().GetConfigValue();
   return new ParameterizedService(config);
});

services.AddScoped<IUrlHelper>(serviceProvider =>
{
   var actionContext = serviceProvider.GetRequiredService<IActionContextAccessor>().ActionContext;
   var urlHelperFactory = serviceProvider.GetRequiredService<IUrlHelperFactory>();
   return urlHelperFactory.GetUrlHelper(actionContext);
});

namespace Services
{
    public class OrderHandler : IOrderHandler
    {
        private readonly IAccounting _accounting;
        private readonly ISales _sales;
        public OrderHandler(IAccounting accounting, ISales sales)
        {

   public class OrderHandlerLazy : IOrderHandler
    {
        public OrderHandlerLazy(Lazy<IAccounting> accounting, Lazy<ISales> sales)
        {

services.AddTransient<IOrderHandler, OrderHandlerLazy>();
services.AddTransient<IAccounting, Accounting>()
            .AddTransient(serviceProvider => new Lazy<IAccounting>(() => serviceProvider.GetRequiredService<IAccounting>()));
services.AddTransient<ISales, Sales>()
           .AddTransient(serviceProvider => new Lazy<ISales>(() => serviceProvider.GetRequiredService<ISales>()));

services.AddTransient<IMyDisposableService, MyDisposableService>();

public class AnotherController 
{ 
    public AnotherController(MyDisposableService customerService) 
    { 
        // ... 
    } 
}

An unhandled exception occurred while processing the request. 
InvalidOperationException: Unable to resolve service for type ‘MyDisposableService’ while attempting to activate ‘AnotherController’. 
Microsoft.Extensions.DependencyInjection.ActivatorUtilities.GetService(IServiceProvider sp, Type type, Type requiredBy, bool isDefaultParameterRequired)

services.AddTransient<IMyDisposableService, MyDisposableService>();
services.AddTransient<MyDisposableService>(serviceProvider =>
serviceProvider.GetRequiredService<IMyDisposableService>() as MyDisposableService);

string greeting = "Hello, C#";

که در این حالت مجموعه‌ای از کاراکترها را ایجاد خواهد کرد:

1. خانه‌های آن یک ضرب پر نمیشوند بلکه به ترتیب، خانه به خانه پر می‌شوند.
2. قبل از انتساب متن باید باید از طول متن مطمئن شویم تا بتوانیم تعداد خانه‌ها را بر اساس آن ایجاد کنیم.
3. همه عملیات آرایه‌ها از پر کردن ابتدای کار گرفته تا هر عملی، نیاز است به صورت دستی صورت بگیرد و تعداد خطوط کد برای هر کاری هم بالا می‌رود.

string str = "abcde";
char ch = str[1]; // ch == 'b'
str[1] = 'a'; // Compilation error!
ch = str[50]; // IndexOutOfRangeException

string a="Hello \"C#\"";
string b="Hello \r\n C#"; //مساوی با اینتر
string c="C:\\a.jpg"; //چاپ خود علامت  \ -مسیردهی

string c=@"C:\a.jpg";// == "C:\\a.jpg"

string source = "Some source";
string assigned = source;

string hel = "Hel";
string hello = "Hello";
string copy = hel + "lo";

string hello = "Hello";
string same = "Hello";

Console.WriteLine(word1.Equals(word2,
    StringComparison.CurrentCultureIgnoreCase));

string score = "sCore";
string scary = "scary";
 
Console.WriteLine(score.CompareTo(scary));
Console.WriteLine(scary.CompareTo(score));
Console.WriteLine(scary.CompareTo(scary));
 
// Console output:
// 1
// -1
// 0

string alpha = "alpha";
string score1 = "sCorE";
string score2 = "score";
 
Console.WriteLine(string.Compare(alpha, score1, false));
Console.WriteLine(string.Compare(score1, score2, false));
Console.WriteLine(string.Compare(score1, score2, true));
Console.WriteLine(string.Compare(score1, score2,
    StringComparison.CurrentCultureIgnoreCase));
// Console output:
// -1
// 1
// 0
// 0

import RegisterForm from "./components/registerForm";

<Route path="/register" component={RegisterForm} />

<NavLink className="nav-item nav-link" to="/register">
   Register
</NavLink>

import Joi from "@hapi/joi";
import React from "react";

import Form from "./common/form";

class RegisterForm extends Form {
  state = {
    data: { username: "", password: "", name: "" },
    errors: {}
  };

  schema = {
    username: Joi.string()
      .required()
      .email({ minDomainSegments: 2, tlds: { allow: ["com", "net"] } })
      .label("Username"),
    password: Joi.string()
      .required()
      .min(5)
      .label("Password"),
    name: Joi.string()
      .required()
      .label("Name")
  };

  doSubmit = () => {
    // Call the server
    console.log("Submitted");
  };

  render() {
    return (
      <div>
        <h1>Register</h1>
        <form onSubmit={this.handleSubmit}>
          {this.renderInput("username", "Username")}
          {this.renderInput("password", "Password", "password")}
          {this.renderInput("name", "Name")}
          {this.renderButton("Register")}
        </form>
      </div>
    );
  }
}

export default RegisterForm;

import { Link } from "react-router-dom";
// ...


<div className="col">
  <Link
    to="/movies/new"
    className="btn btn-primary"
    style={{ marginBottom: 20 }}
  >
    New Movie
  </Link>
  <p>Showing {totalCount} movies in the database.</p>

import Joi from "@hapi/joi";
import React from "react";

import { getGenres } from "../services/fakeGenreService";
import { getMovie, saveMovie } from "../services/fakeMovieService";
import Form from "./common/form";

class MovieForm extends Form {
  state = {
    data: {
      title: "",
      genreId: "",
      numberInStock: "",
      dailyRentalRate: ""
    },
    genres: [],
    errors: {}
  };

  schema = {
    _id: Joi.string(),
    title: Joi.string()
      .required()
      .label("Title"),
    genreId: Joi.string()
      .required()
      .label("Genre"),
    numberInStock: Joi.number()
      .required()
      .min(0)
      .max(100)
      .label("Number in Stock"),
    dailyRentalRate: Joi.number()
      .required()
      .min(0)
      .max(10)
      .label("Daily Rental Rate")
  };

  componentDidMount() {
    const genres = getGenres();
    this.setState({ genres });

    const movieId = this.props.match.params.id;
    if (movieId === "new") return;

    const movie = getMovie(movieId);
    if (!movie) return this.props.history.replace("/not-found");

    this.setState({ data: this.mapToViewModel(movie) });
  }

  mapToViewModel(movie) {
    return {
      _id: movie._id,
      title: movie.title,
      genreId: movie.genre._id,
      numberInStock: movie.numberInStock,
      dailyRentalRate: movie.dailyRentalRate
    };
  }

  doSubmit = () => {
    saveMovie(this.state.data);

    this.props.history.push("/movies");
  };

  render() {
    return (
      <div>
        <h1>Movie Form</h1>
        <form onSubmit={this.handleSubmit}>
          {this.renderInput("title", "Title")}
          {this.renderSelect("genreId", "Genre", this.state.genres)}
          {this.renderInput("numberInStock", "Number in Stock", "number")}
          {this.renderInput("dailyRentalRate", "Rate")}
          {this.renderButton("Save")}
        </form>
      </div>
    );
  }

import React from "react";

const Select = ({ name, label, options, error, ...rest }) => {
  return (
    <div className="form-group">
      <label htmlFor={name}>{label}</label>
      <select name={name} id={name} {...rest} className="form-control">
        <option value="" />
        {options.map(option => (
          <option key={option._id} value={option._id}>
            {option.name}
          </option>
        ))}
      </select>
      {error && <div className="alert alert-danger">{error}</div>}
    </div>
  );
};

export default Select;

import Select from "./select";
// ...

class Form extends Component {

  // ...

  renderSelect(name, label, options) {
    const { data, errors } = this.state;

    return (
      <Select
        name={name}
        value={data[name]}
        label={label}
        options={options}
        onChange={this.handleChange}
        error={errors[name]}
      />
    );
  }
}

import React from "react";

const SearchBox = ({ value, onChange }) => {
  return (
    <input
      type="text"
      name="query"
      className="form-control my-3"
      placeholder="Search..."
      value={value}
      onChange={e => onChange(e.currentTarget.value)}
    />
  );
};

export default SearchBox;

<p>Showing {totalCount} movies in the database.</p>
<SearchBox value={searchQuery} onChange={this.handleSearch} />

import SearchBox from "./searchBox";
//...

class Movies extends Component {
  state = {
    //...
    selectedGenre: {},
    searchQuery: ""
  };


  handleSearch = query => {
    this.setState({ searchQuery: query, selectedGenre: null, currentPage: 1 });
  };

  handleGenreSelect = genre => {
    console.log("handleGenreSelect", genre);
    this.setState({ selectedGenre: genre, searchQuery: "", currentPage: 1 });
  };

  getPagedData() {
    const {
      pageSize,
      currentPage,
      selectedGenre,
      movies: allMovies,
      sortColumn,
      searchQuery
    } = this.state;

    let filteredMovies = allMovies;
    if (searchQuery) {
      filteredMovies = allMovies.filter(m =>
        m.title.toLowerCase().startsWith(searchQuery.toLowerCase())
      );
    } else if (selectedGenre && selectedGenre._id) {
      filteredMovies = allMovies.filter(m => m.genre._id === selectedGenre._id);
    }

public class Order 
{ 
    public decimal Price() { 
        return new PriceCalculator(this).Compute(); 
    } 
} 
public class PriceCalculator 
{ 
    private Order orderInstance ;
    public PriceCalculator(Order order) 
    { 
        orderInstance = order;
    } 
    public decimal Compute() 
    { 
        var primaryBasePrice = 10000; 
        var branchDiscountBasePrice = 9000; 
        var taxPercentage = 9; 
        // calculate price 
    } 
}

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