using System;
using System.Collections.Generic;

namespace MvcApplication17.Models
{
    public class Employee
    {
        public int Id { set; get; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public DateTime AddDate { get; set; }
        public double Salary { get; set; }
        public IList<Project> Projects { get; set; }
    }
}

namespace MvcApplication17.Models
{
    public class Project
    {
        public int Id { set; get; }
        public string Name { set; get; }
    }
}

using System;
using System.Collections.Generic;

namespace MvcApplication17.Models
{
    public static class EmployeeDataSource
    {
        public static IList<Employee> CreateEmployees()
        {
            var list = new List<Employee>();
            var rnd = new Random();
            for (int i = 1; i <= 1000; i++)
            {
                list.Add(new Employee
                    {
                        Id = i + 1000,
                        FirstName = "fName " + i,
                        LastName = "lName " + i,
                        AddDate = DateTime.Now.AddYears(-rnd.Next(1, 10)),
                        Salary = rnd.Next(400, 3000),
                        Projects = CreateRandomProjects()
                    });
            }
            return list;
        }

        private static IList<Project> CreateRandomProjects()
        {
            var list = new List<Project>();
            var rnd = new Random();
            for (int i = 0; i < rnd.Next(1, 7); i++)
            {
                list.Add(new Project
                {
                    Id = i,
                    Name = "Project " + i
                });
            }
            return list;
        }
    }
}

using System.Web.Mvc;
using MvcApplication17.Models;

namespace MvcApplication17.Controllers
{
    public class HomeController : Controller
    {
        [HttpPost]
        public ActionResult Delete(int? id)
        {
            return RedirectToAction("Index");
        }

        [HttpGet]
        public ActionResult Edit(int? id)
        {
            return View();
        }

        [HttpGet]
        public ActionResult Index(string sort, string sortdir, int? page = 1)
        {
            var list = EmployeeDataSource.CreateEmployees();
            return View(list);
        }
    }
}

http://localhost:3034/?sort=LastName&sortdir=ASC&page=3

@using System.Globalization
@model IList<MvcApplication17.Models.Employee>
           
@{
    ViewBag.Title = "Index";
}

@helper WebGridPageFirstItem(WebGrid grid)
{
    @(((grid.PageIndex + 1) * grid.RowsPerPage) - (grid.RowsPerPage - 1));
}

@helper WebGridPageLastItem(WebGrid grid)
{
    if (grid.TotalRowCount < (grid.PageIndex + 1 * grid.RowsPerPage))
    {
      @grid.TotalRowCount;
    }
    else
    {
      @((grid.PageIndex + 1) * grid.RowsPerPage);
    }
}

<h2>Employees List</h2>

@{ 
    var grid = new WebGrid(
        source: Model,
        canPage: true,
        rowsPerPage: 10,
        canSort: true,
        defaultSort: "FirstName"
    );
    var salaryPageSum = 0;
    var taxPageSum = 0;
    var rowIndex = ((grid.PageIndex + 1) * grid.RowsPerPage) - (grid.RowsPerPage - 1);
}

<div id="container">
    @grid.GetHtml(
            tableStyle: "webgrid",
            headerStyle: "webgrid-header",
            footerStyle: "webgrid-footer",
            alternatingRowStyle: "webgrid-alternating-row",
            selectedRowStyle: "webgrid-selected-row",
            rowStyle: "webgrid-row-style",
            htmlAttributes: new { id = "MyGrid" },
            mode: WebGridPagerModes.All,
            columns: grid.Columns(
                 grid.Column(header: "#",
                             style: "text-align-center-col",
                             format: @<text>@(rowIndex++)</text>),
                 grid.Column(columnName: "FirstName", header: "First Name",
                             format: @<span style='font-weight: bold'>@item.FirstName</span>,
                             style: "text-align-center-col"),
                 grid.Column(columnName: "LastName", header: "Last Name"),
                 grid.Column(header: "Image",
                             style: "text-align-center-col",
                             format: @<text><img alt="@item.Id" src="@Url.Content("~/images/" + @item.Id + ".jpg")" /></text>),
                 grid.Column(columnName: "AddDate", header: "Start",
                             style: "text-align-center-col",
                             format: item =>
                             {
                                 int ym = item.AddDate.Year;
                                 int mm = item.AddDate.Month;
                                 int dm = item.AddDate.Day;
                                 var persianCalendar = new PersianCalendar();
                                 int ys = persianCalendar.GetYear(new DateTime(ym, mm, dm, new GregorianCalendar()));
                                 int ms = persianCalendar.GetMonth(new DateTime(ym, mm, dm, new GregorianCalendar()));
                                 int ds = persianCalendar.GetDayOfMonth(new DateTime(ym, mm, dm, new GregorianCalendar()));
                                 return ys + "/" + ms.ToString("00") + "/" + ds.ToString("00");

                             }),
                 grid.Column(columnName: "Salary", header: "Salary",
                             format: item =>
                             {
                                 salaryPageSum += item.Salary;
                                 return string.Format("${0:n0}", item.Salary);
                             },
                             style: "text-align-center-col"),
                 grid.Column(header: "Tax", canSort: true,
                             format: item =>
                             {
                                 var tax = item.Salary * 0.2;
                                 taxPageSum += tax;
                                 return string.Format("${0:n0}", tax);
                             }),
                 grid.Column(header: "Projects", columnName: "Projects",
                             style: "text-align-center-col",
                             format: item =>
                             {
                                 var subGrid = new WebGrid(
                                                        source: item.Projects,
                                                        canPage: false,
                                                        canSort: false
                                                        );
                                 return subGrid.GetHtml(
                                                        htmlAttributes: new { id = "MySubGrid" },
                                                        tableStyle: "webgrid",
                                                        headerStyle: "webgrid-header",
                                                        footerStyle: "webgrid-footer",
                                                        alternatingRowStyle: "webgrid-alternating-row",
                                                        selectedRowStyle: "webgrid-selected-row",
                                                        rowStyle: "webgrid-row-style"
                                     );
                             }),
                 grid.Column(header: "",
                             style: "text-align-center-col",
                             format: item => @Html.ActionLink(linkText: "Edit", actionName: "Edit",
                                                              controllerName: "Home", routeValues: new { id = item.Id },
                                                              htmlAttributes: null)),
                 grid.Column(header: "",
                             format: @<form action="/Home/Delete/@item.Id" method="post"><input type="submit"
                                            onclick="return confirm('Do you want to delete this record?');"
                                            value="Delete"/></form>),
                 grid.Column(header: "", format: item => item.GetSelectLink("Select"))
                      )
                  )

    <strong>Page:</strong> @(grid.PageIndex + 1) / @grid.PageCount, 
    <strong>Records:</strong> @WebGridPageFirstItem(@grid) - @WebGridPageLastItem(@grid) of @grid.TotalRowCount

    @*
    @if (@grid.HasSelection)
    {
        @RenderPage("~/views/path/_partial_view.cshtml", new { Employee = grid.SelectedRow })
    }
    *@
</div>

@section script{
<script type="text/javascript">
    $(function () {
        $('#MyGrid tbody:first').append(
        '<tr class="total-row"><td></td>\
         <td></td><td></td><td></td>\
         <td><strong>Total:</strong></td>\
         <td>@string.Format("${0:n0}", @salaryPageSum)</td>\
         <td>@string.Format("${0:n0}", @taxPageSum)</td>\
         <td></td><td></td><td></td></tr>');
    });
</script>
}

@{ 
    var grid = new WebGrid(
        source: Model,
        canPage: true,
        rowsPerPage: 10,
        canSort: true,
        defaultSort: "FirstName"
    );
    var salaryPageSum = 0;
    var taxPageSum = 0;
    var rowIndex = ((grid.PageIndex + 1) * grid.RowsPerPage) - (grid.RowsPerPage - 1);
}

tableStyle: "webgrid",
headerStyle: "webgrid-header",
footerStyle: "webgrid-footer",
alternatingRowStyle: "webgrid-alternating-row",
selectedRowStyle: "webgrid-selected-row",
rowStyle: "webgrid-row-style",
htmlAttributes: new { id = "MyGrid" },

<div id="container">
      <table class="webgrid" id="MyGrid">
        <thead>
          <tr class="webgrid-header">

/* Styles for WebGrid
-----------------------------------------------------------*/
.webgrid
{
 width: 100%;
 margin: 0px;
 padding: 0px;
 border: 0px;
 border-collapse: collapse;
 font-family: Tahoma;
 font-size: 9pt;
}

.webgrid a
{
 color: #000;
}

.webgrid-header
{
 padding: 0px 5px;
 text-align: center;
 border-bottom: 2px solid #739ace;
 height: 20px;
 border-top: 2px solid #D6E8FF;
 border-left: 2px solid #D6E8FF;
 border-right: 2px solid #D6E8FF;
}

.webgrid-header th
{
 background-color: #eaf0ff;
 border-right: 1px solid #ddd;
}

.webgrid-footer
{
 padding: 6px 5px;
 text-align: center;
 background-color: #e8eef4;
 border-top: 2px solid #3966A2;
 height: 25px;
 border-bottom: 2px solid #D6E8FF;
 border-left: 2px solid #D6E8FF;
 border-right: 2px solid #D6E8FF;
}

.webgrid-alternating-row
{
 height: 22px;
 background-color: #f2f2f2;
 border-bottom: 1px solid #d2d2d2;
 border-left: 2px solid #D6E8FF;
 border-right: 2px solid #D6E8FF;
}

.webgrid-row-style
{
 height: 22px;
 border-bottom: 1px solid #d2d2d2;
 border-left: 2px solid #D6E8FF;
 border-right: 2px solid #D6E8FF;
}

.webgrid-selected-row
{
 font-weight: bold;
}

.text-align-center-col
{
 text-align: center;
}

.total-row
{
 background-color:#f9eef4;
}

[Flags]
public enum WebGridPagerModes
{
        Numeric = 1,
        //
        NextPrevious = 2,
        //
        FirstLast = 4,
        //
        All = 7,
}

grid.Column(columnName: "FirstName", header: "First Name",
                             format: @<span style='font-weight: bold'>@item.FirstName</span>,
                             style: "text-align-center-col"),
grid.Column(columnName: "LastName", header: "Last Name"),

Func<dynamic, object> format

format: @<span style='font-weight: bold'>@item.FirstName</span>
or
format: item =>
                     {
                          salaryPageSum += item.Salary;
                           return string.Format("${0:n0}", item.Salary);
                      }

grid.Column(header: "#",
                 style: "text-align-center-col",
                 format: @<text>@(rowIndex++)</text>),

grid.Column(header: "Image",
                  style: "text-align-center-col",
                  format: @<text><img alt="@item.Id" src="@Url.Content("~/images/" + @item.Id + ".jpg")" /></text>),

grid.Column(columnName: "AddDate", header: "Start",
                  style: "text-align-center-col",
                  format: item =>
                  {
                       int ym = item.AddDate.Year;
                       int mm = item.AddDate.Month;
                       int dm = item.AddDate.Day;
                       var persianCalendar = new PersianCalendar();
                       int ys = persianCalendar.GetYear(new DateTime(ym, mm, dm, new GregorianCalendar()));
                       int ms = persianCalendar.GetMonth(new DateTime(ym, mm, dm, new GregorianCalendar()));
                       int ds = persianCalendar.GetDayOfMonth(new DateTime(ym, mm, dm, new GregorianCalendar()));
                       return ys + "/" + ms.ToString("00") + "/" + ds.ToString("00");
                    }),

grid.Column(columnName: "Salary", header: "Salary",
                 format: item =>
                             {
                                 salaryPageSum += item.Salary;
                                 return string.Format("${0:n0}", item.Salary);
                             },
                             style: "text-align-center-col"),
grid.Column(header: "Tax", canSort: true,
                             format: item =>
                             {
                                 var tax = item.Salary * 0.2;
                                 taxPageSum += tax;
                                 return string.Format("${0:n0}", tax);
                             }),

grid.Column(header: "Projects", columnName: "Projects",
                  style: "text-align-center-col",
                  format: item =>
                  {
                                 var subGrid = new WebGrid(
                                                        source: item.Projects,
                                                        canPage: false,
                                                        canSort: false
                                                        );
                                 return subGrid.GetHtml(
                                                        htmlAttributes: new { id = "MySubGrid" },
                                                        tableStyle: "webgrid",
                                                        headerStyle: "webgrid-header",
                                                        footerStyle: "webgrid-footer",
                                                        alternatingRowStyle: "webgrid-alternating-row",
                                                        selectedRowStyle: "webgrid-selected-row",
                                                        rowStyle: "webgrid-row-style"
                                     );
                       }),

grid.Column(header: "",
                  style: "text-align-center-col",
                   format: item => @Html.ActionLink(linkText: "Edit", actionName: "Edit",
                                                              controllerName: "Home", routeValues: new { id = item.Id },
                                                              htmlAttributes: null)),
grid.Column(header: "",
                  format: @<form action="/Home/Delete/@item.Id" method="post"><input type="submit"
                                            onclick="return confirm('Do you want to delete this record?');"
                                            value="Delete"/></form>),
grid.Column(header: "", format: item => item.GetSelectLink("Select"))

@if (@grid.HasSelection)
    {
        @RenderPage("~/views/path/_partial_view.cshtml", new { Employee = grid.SelectedRow })
    }

<strong>Page:</strong> @(grid.PageIndex + 1) / @grid.PageCount, 
    <strong>Records:</strong> @WebGridPageFirstItem(@grid) - @WebGridPageLastItem(@grid) of @grid.TotalRowCount

@section script{
<script type="text/javascript">
    $(function () {
        $('#MyGrid tbody:first').append(
        '<tr class="total-row"><td></td>\
         <td></td><td></td><td></td>\
         <td><strong>Total:</strong></td>\
         <td>@string.Format("${0:n0}", @salaryPageSum)</td>\
         <td>@string.Format("${0:n0}", @taxPageSum)</td>\
         <td></td><td></td><td></td></tr>');
    });
</script>
}

<head>
    <title>@ViewBag.Title</title>
    <link href="@Url.Content("~/Content/Site.css")" rel="stylesheet" type="text/css" />
    <script src="@Url.Content("~/Scripts/jquery-1.5.1.min.js")" type="text/javascript"></script>
    @RenderSection("script", required: false)
</head>

USE AdventureWorks2012;

GO
CREATE TABLE dbo.Contacts (
    ContactID         INT           IDENTITY (1, 1),
    FirstName         NVARCHAR (50),
    LastName          NVARCHAR (50),
    IsActive          BIT          ,
    EmailAddress      NVARCHAR (50),
    CertificationDate DATETIME     ,
    FillerData        CHAR (1000)  ,
    CONSTRAINT PK_Contacts PRIMARY KEY CLUSTERED (ContactID)
);

INSERT INTO dbo.Contacts (FirstName, LastName, IsActive, EmailAddress, CertificationDate)
SELECT pp.FirstName,
       pp.LastName,
       IIF (pp.BusinessEntityID / 10 = 1, 1, 0),
       pea.EmailAddress,
       IIF (pp.BusinessEntityID / 10 = 1, pp.ModifiedDate, NULL)
FROM   Person.Person AS pp
       INNER JOIN
       Person.EmailAddress AS pea
       ON pp.BusinessEntityID = pea.BusinessEntityID;

SET STATISTICS IO ON;

SELECT ContactID,
       FirstName
FROM   dbo.Contacts
WHERE  FirstName = 'Catherine';

SET STATISTICS IO OFF;

CREATE INDEX IX_Contacts_LastName ON dbo.Contacts(LastName);

CREATE INDEX IX_Contacts_FirstNameLastNameIsActive ON dbo.Contacts(FirstName, LastName,IsActive)

CREATE INDEX IX_Contacts_FirstNameINC ON dbo.Contacts(FirstName)
INCLUDE (LastName, IsActive, EmailAddress);

IF EXISTS(SELECT * FROM sys.indexes WHERE object_id = OBJECT_ID('dbo.Contacts')
AND name = 'IX_Contacts_FirstNameLastName')
DROP INDEX IX_Contacts_FirstNameLastName ON dbo.Contacts
GO
IF EXISTS(SELECT * FROM sys.indexes WHERE object_id = OBJECT_ID('dbo.Contacts')
AND name = 'IX_Contacts_FirstNameLastNameIsActive')
DROP INDEX IX_Contacts_FirstNameLastNameIsActive ON dbo.Contacts
GO
IF EXISTS(SELECT * FROM sys.indexes WHERE object_id = OBJECT_ID('dbo.Contacts')
AND name = 'IX_Contacts_FirstName')
DROP INDEX IX_Contacts_FirstName ON dbo.Contacts
GO

The settings

<appSettings>
    <add key="RetryAttempts" value="5" />
    <add key="ApplicationBuildDate" value="11/4/1999 6:23 AM" />
</appSettings>

The code

dynamic config = new Configuration();
var retryAttempts1 = config.RetryAttempts;                 // returns 5 as a string
var retryAttempts2 = config.RetryAttempts(10);             // returns 5 if found in config, else 10
var retryAttempts3 = config.RetryAttempts(userInput, 10);  // returns 5 if it exists in config, else userInput i

const int field_constant = 10;  //constant field
static void Main(string[] args)
{
    const int x = 10, y = 15;   //constant local :correct
    const int z = x + y;        //constant local : correct;
    const int a = x + GetVariableValue();//Error
}
public static int GetVariableValue()
{
    const int localx = 10;
    return 10;
}

 class Program
    {
        public const int numberOfDays = 7;
        public readonly double piValue = 3.14;

        static void Main(string[] args)
        {
            
        }
    }

public const int numberOfDays = 7;
public readonly double piValue = 3.14;

static void Main(string[] args)
{
   var readEx = new MyLib.TestClass();
   var readConstValue = MyLib.TestClass.numberOfDays;
   var readReadOnlyValue = readEx.piValue;
}

.method private hidebysig static void  Main(string[] args) cil managed
{
  .entrypoint
  // Code size 17 (0x11)
  .maxstack  1
  .locals init ([0] class [MyLib]MyLib.TestClass readEx,
  [1] int32 readConstValue,
  [2] float64 readOnlyValue)
  IL_0000:  nop
  IL_0001:  newobj   instance void [MyLib]MyLib.TestClass::.ctor()
  IL_0006:  stloc.0 //readEx
  IL_0007:  ldc.i4.7  //ارزش ذخیره شده در کد
  IL_0008:  stloc.1 //readConstValue
  IL_0009:  ldloc.0 //readEg
  IL_000a:  ldfld float64 [MyLib]MyLib.TestClass::piValue
  IL_000f:  stloc.2 //readReadOnlyValue
  IL_0010:  ret
} // end of method Program::Main

public class ReadonlyStatic
{
  public static readonly string x = "Hi";
  public static readonly string y;
  public ReadonlyStatic()
  {
     //y = "Hello"; This is wrong
  }
  static ReadonlyStatic()
  {
    y = "Hello";
  }
}

چه زمانی از Const و چه زمانی از ReadOnly استفاده کنیم :

• زمانی باید از Const استفاده کرد که مطمئن هستیم ارزش ذخیره شده در آن در طول عمر یک برنامه تغییر نمی‌کند. بطور مثال ذخیره تعداد روز هفته در یک فیلد از نوع Constant. اگر شک داریم که ممکن است این ارزش تغییر کند، می‌توانیم از حالت static readOnly برای غلبه بر مشکل Versioning استفاده کنیم.
• از آنجائیکه مقادیر constant در کد‌های IL گنجانده می‌شوند، برای رسیدن به کارآیی بهتر، مقادیری را که در طول عمر یک برنامه تغییر نمی‌کنند، به صورت  const تعریف می‌کنیم.
• هر زمان تصمیم داشتیم Constant هایی به ازای هر وهله از کلاس داشته باشیم از ReadOnly استفاده می‌کنیم. 

        public bool RecordMoveUpDown(int idPost1, int rowNumber1, int idPost2, int rowNumber2)
        {
            var result = true;

            try
            {
                _posts.Update(t => t.Id == idPost1, t => new TPersonalPost { Row = rowNumber2 });
                _posts.Update(t => t.Id == idPost2, t => new TPersonalPost { Row = rowNumber1 });
            }
            catch
            {
                result = false;
            }
            return result;
        }

• چرا مسیریابی نشانه ای؟
• فعال سازی مسیریابی نشانه ای
• پارامتر‌های اختیاری URI و مقادیر پیش فرض
• پیشوند مسیر ها
• مسیر پیش فرض
• محدودیت‌های مسیر ها
• محدودیت‌های سفارشی
• نام مسیر ها
• ناحیه‌ها (Areas)

• {productId:int}/{productTitle}

• {username}

• {username}/catalogs/{catalogId:int}/{catalogTitle}

// eg: /users/5
// but not /users/10000000000 because it is larger than int.MaxValue,
// and not /users/0 because of the min(1) constraint.
[Route("users/{id:int:min(1)}")]
public ActionResult GetUserById(int id) { ... }

// eg: /greetings/bye
// and /greetings because of the Optional modifier,
// but not /greetings/see-you-tomorrow because of the maxlength(3) constraint.
[Route("greetings/{message:maxlength(3)?}")]
public ActionResult Greet(string message) { ... }

public class ValuesConstraint : IRouteConstraint
{
    private readonly string[] validOptions;
    public ValuesConstraint(string options)
    {
        validOptions = options.Split('|');
    }
 
    public bool Match(HttpContextBase httpContext, Route route, string parameterName, RouteValueDictionary values, RouteDirection routeDirection)
    {
        object value;
        if (values.TryGetValue(parameterName, out value) && value != null)
        {
            return validOptions.Contains(value.ToString(), StringComparer.OrdinalIgnoreCase);
        }
        return false;
    }
}

public class RouteConfig
{
    public static void RegisterRoutes(RouteCollection routes)
    {
        routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
 
        var constraintsResolver = new DefaultInlineConstraintResolver();
 
        constraintsResolver.ConstraintMap.Add("values", typeof(ValuesConstraint));
 
        routes.MapMvcAttributeRoutes(constraintsResolver);
    }
}

public class TemperatureController : Controller
{
    // eg: temp/celsius and /temp/fahrenheit but not /temp/kelvin
    [Route("temp/{scale:values(celsius|fahrenheit)}")]
    public ActionResult Show(string scale)
    {
        return Content("scale is " + scale);
    }
}

[Route("menu", Name = "mainmenu")]
public ActionResult MainMenu() { ... }

<a href="@Url.RouteUrl("mainmenu")">Main menu</a>

[RouteArea("Admin")]
[RoutePrefix("menu")]
[Route("{action}")]
public class MenuController : Controller
{
    // eg: /admin/menu/login
    public ActionResult Login() { ... }
 
    // eg: /admin/menu/show-options
    [Route("show-options")]
    public ActionResult Options() { ... }
 
    // eg: /stats
    [Route("~/stats")]
    public ActionResult Stats() { ... }
}

Url.Action("Options", "Menu", new { Area = "Admin" })

[RouteArea("BackOffice", AreaPrefix = "back-office")]

public static void RegisterRoutes(RouteCollection routes)
{
    routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
 
    routes.MapMvcAttributeRoutes();
 
    AreaRegistration.RegisterAllAreas();
 
    routes.MapRoute(
        name: "Default",
        url: "{controller}/{action}/{id}",
        defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
    );
}