#1 let mutable phrase = "Can it change? "

#2 printfn "%s" phrase

#3 phrase <- "yes, it can."

#4 printfn "%s" phrase

Can it change?  
yes, it can.

#1 let mutable phrase = "Can it change?  "

#3 phrase <- 1

Prog.fs(9,10): error: FS0001: This expression has type
int
but is here used with type
string

let redefineX() =
let x = "One"
printfn "Redefining:\r\nx = %s" x
if true then
   let x = "Two"
printfn "x = %s" x
printfn "x = %s" x

Redefining:
x = One
x = Two
x = One

let mutableX() =
let mutable x = "One"
printfn "Mutating:\r\nx = %s" x
if true then
   x <- "Two"
printfn "x = %s" x
printfn "x = %s" x

Mutating:
x = One
x = Two
x = Two

let refVar = ref 6

refVar := 50



printfn "%d" !refVar

let xRef : int ref = ref 10

printfn "%d" (xRef.Value)
printfn "%d" (xRef.contents)

xRef.Value <- 11
printfn "%d" (xRef.Value)
xRef.contents <- 12
printfn "%d" (xRef.contents)

10
10
11
12 

let keepIfPositive (a : int) = if a > 0 then Some(a) else None

let exists (x : int option) = 
    match x with
    | Some(x) -> true
    | None -> false

let rec tryFindMatch pred list =
    match list with
    | head :: tail -> if pred(head)
                        then Some(head)
                        else tryFindMatch pred tail
    | [] -> None

let result1 = tryFindMatch (fun elem -> elem = 100) [ 200; 100; 50; 25 ] //برابر با 100 است

let result2 = tryFindMatch (fun elem -> elem = 26) [ 200; 100; 50; 25 ]// برابر با None است

open System.IO
let openFile filename =
    try 
        let file = File.Open (filename, FileMode.Create)
        Some(file)
    with
        | ex -> eprintf "An exception occurred with message %s" ex.Message
                None

type enum-name =
   | value1 = integer-literal1
   | value2 = integer-literal2
   ...

type Color =
   | Red = 0
   | Green = 1
   | Blue = 2

let col1 : Color = Color.Red

type uColor =
   | Red = 0u
   | Green = 1u
   | Blue = 2u
let col3 = Microsoft.FSharp.Core.LanguagePrimitives.EnumOfValue<uint32, uColor>(2u)

using(var writer = new StreamWriter(filePath))
{
   
}

let writeToFile fileName =
    use sw = new System.IO.StreamWriter(fileName : string)
    sw.Write("Hello ")

[<Measure>] type unit-name [ = measure ]

[<Measure>] type cm

[<Measure>] type ml = cm^3

let value = 1.0<cm>

[<Measure>] type g                 تعریف واحد گرم
[<Measure>] type kg               تعریف واحد کیلوگرم
let gramsPerKilogram : float<g kg^-1> = 1000.0<g/kg>    تعریف تابع تبدیل

[<Measure>] type degC // دما بر حسب سلسیوس
[<Measure>] type degF // دما بر حسب فارنهایت

let convertCtoF ( temp : float<degC> ) = 9.0<degF> / 5.0<degC> * temp + 32.0<degF> // تابع تبدیل سلسیوس به فارنهایت
let convertFtoC ( temp: float<degF> ) = 5.0<degC> / 9.0<degF> * ( temp - 32.0<degF>) // تابع تبدیل فارنهایت به سلسیوس

let degreesFahrenheit temp = temp * 1.0<degF> // درجه به فارنهایت
let degreesCelsius temp = temp * 1.0<degC> // درجه به سلسیوس

printfn "Enter a temperature in degrees Fahrenheit." 
let input = System.Console.ReadLine()
let mutable floatValue = 0.
if System.Double.TryParse(input, &floatValue)// اگر ورودی عدد بود
   then 
      printfn "That temperature in Celsius is %8.2f degrees C." ((convertFtoC (degreesFahrenheit floatValue))/(1.0<degC>))
   else
      printfn "Error parsing input."

Enter a temperature in degrees Fahrenheit.
90
That temperature in degrees Celsius is    32.22.

public IPdfReportData CreatePdfReport(int type,int RequestId)
        {
            return new PdfReport().DocumentPreferences(doc =>
            {
                doc.RunDirection(PdfRunDirection.RightToLeft);
                doc.Orientation(PageOrientation.Portrait);
                doc.PageSize(PdfPageSize.A4);
               
            })
            .DefaultFonts(fonts =>
            {
                fonts.Path(AppPath.ApplicationPath + "\\Fonts\\BNAZANIN.TTF",
                                  AppPath.ApplicationPath + "\\Fonts\\TIMES.TTF");
                fonts.Size(20);
            })
            .PagesFooter(footer =>
            {
                footer.DefaultFooter("");
                footer.PdfFont.Size = 8;

            })
            .PagesHeader(header =>
            {
                if (type == 1)
                {
                    header.CustomHeader(_customHeader);
                }
                else
                {
                    header.DefaultHeader(h => h.Message("mohsen"));
                }

            })
             .MainTableTemplate(template =>
             {
                 template.BasicTemplate(BasicTemplate.SilverTemplate);
             })
            .MainTablePreferences(table =>
            {
                table.ColumnsWidthsType(TableColumnWidthType.Relative);


            })
            .MainTableDataSource(dataSource =>
            {
               
                
                var ctx = new ClearanceEntities();




                var list = (from c in ctx.CLEARANCE_ITEMS
                            where c.CLEARANCE_REQUEST.REQUEST_ID == RequestId
                            select new
                            {
                                c.TARIFF_NO,
                                c.GOODS_DESCRIPTION,
                                vahed = c.QUANTITY,
                                c.PACKING_TYPES.PACKING_NAME,
                                c.GROSS_WEIGHT,
                                arzesh = (c.GOODS_PRICE * c.GOODS_CURRENCY_RATE) + (c.FREIGHT_PRICE * c.FREIGHT_CURRENCY_RATE),
                                hoghogh = " ",
                                sood = " "

                            }).ToList();
               



                dataSource.AnonymousTypeList(list );
            })

            .MainTableColumns(columns =>
            {
                columns.AddColumn(column =>
                {
                    column.PropertyName("TARIFF_NO");

                    column.CellsHorizontalAlignment(HorizontalAlignment.Center);
                    column.IsVisible(true);
                    column.Order(0);
                    column.Width(3);
                    column.HeaderCell("تعرفه");
                });
                columns.AddColumn(column =>
                {
                    column.PropertyName("GOODS_DESCRIPTION");
                    column.CellsHorizontalAlignment(HorizontalAlignment.Center);

                    column.IsVisible(true);
                    column.Order(1);
                    column.Width(5);
                    column.HeaderCell("نام کالا");
                    column.ColumnItemsTemplate(template =>
                        {
                            new CellBasicProperties
                                {
                                  
                                    //PdfFontStyle = DocumentFontStyle.Bold | DocumentFontStyle.Underline,
                                    //FontColor = new BaseColor(System.Drawing.Color.Brown),
                                    //BackgroundColor = new BaseColor(System.Drawing.Color.Yellow)
                                };
                            return;
                        });

                });
                columns.AddColumn(column =>
                {
                    column.PropertyName("vahed");
                    column.CellsHorizontalAlignment(HorizontalAlignment.Center);
                    column.IsVisible(true);
                    column.Order(1);
                    column.Width(5);
                    column.HeaderCell("واحد");

                });
                columns.AddColumn(column =>
                {
                    column.PropertyName("GROSS_WEIGHT");
                    column.CellsHorizontalAlignment(HorizontalAlignment.Center);
                    column.IsVisible(true);
                    column.Order(1);
                    column.Width(5);
                    column.HeaderCell("وزن ناخالص");

                });
                columns.AddColumn(column =>
                {
                    column.PropertyName("arzesh");
                    column.CellsHorizontalAlignment(HorizontalAlignment.Center);
                    column.IsVisible(true);
                    column.Order(1);
                    column.Width(5);
                    column.HeaderCell("ارزش دلاری");

                });
                columns.AddColumn(column =>
                {
                    column.PropertyName("hoghogh");
                    column.CellsHorizontalAlignment(HorizontalAlignment.Center);
                    column.IsVisible(true);
                    column.Order(1);
                    column.Width(3);
                    column.HeaderCell("حقوق گمرکی");

                });
                columns.AddColumn(column =>
                {
                    column.PropertyName("sood");
                    column.CellsHorizontalAlignment(HorizontalAlignment.Center);
                    column.IsVisible(true);
                    column.Order(1);
                    column.Width(3);
                    column.HeaderCell("سود بازرگانی");

                });


            })
            .MainTableEvents(events =>
            {
                events.DataSourceIsEmpty(message: "There is no data available to display.");

}

                 events.DocumentClosing(args =>
            {
                if (HttpContext.Current == null || HttpContext.Current.Response == null) return;

                // close the document without closing the underlying stream
                args.PdfWriter.CloseStream = false;
                args.PdfDoc.Close();
                args.PdfStreamOutput.Position = 0;

                // write pdf bytes to output stream
                var pdf = ((MemoryStream)args.PdfStreamOutput).ToArray();
                string str = Guid.NewGuid().ToString();
                HttpContext.Current.Response.Cache.SetCacheability(HttpCacheability.NoCache);
                HttpContext.Current.Response.ContentType = MediaTypeNames.Application.Pdf;
                HttpContext.Current.Response.AddHeader("Content-Length", pdf.Length.ToString());
                HttpContext.Current.Response.AddHeader("content-disposition", "attachment;filename=" + str + ".pdf");
                HttpContext.Current.Response.Buffer = true;
                HttpContext.Current.Response.Clear();
                HttpContext.Current.Response.OutputStream.Write(pdf, 0, pdf.Length);
                HttpContext.Current.Response.OutputStream.Flush();
                HttpContext.Current.Response.OutputStream.Close();
                HttpContext.Current.Response.End();
            });
        })

           .Generate(data => data.AsPdfStream(new MemoryStream()));

using System;

namespace jqGrid13.Models
{
    public class BlogComment
    {
        // Other properties 
        public int Id { set; get; }
        public string Body { set; get; }
        public DateTime AddDateTime { set; get; }

        // for treeGridModel: 'adjacency'
        public int? ParentId { get; set; }
        public bool IsNotExpandable { get; set; }
        public bool IsExpanded { get; set; }
    }
}

using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Web.Mvc;
using jqGrid13.Models;
using JqGridHelper.DynamicSearch; // for dynamic OrderBy
using JqGridHelper.Models;
using JqGridHelper.Utils;

namespace jqGrid13.Controllers
{
    public class HomeController : Controller
    {
        public ActionResult Index()
        {
            return View();
        }

        public ActionResult GetComments(JqGridRequest request, int? nodeid, int? parentid, int? n_level)
        {
            var list = BlogCommentsDataSource.LatestBlogComments;

            // در این حالت خاص فعلا در نگارش جای جی‌کیو‌گرید صفحه بندی کار نمی‌کند و فعال نیست و محاسبات ذیل اهمیتی ندارند
            var pageIndex = request.page - 1;
            var pageSize = request.rows;
            var totalRecords = list.Count;
            var totalPages = (int)Math.Ceiling(totalRecords / (float)pageSize);

            var productsQuery = list.AsQueryable();
            
            if (nodeid == null)
            {
                productsQuery = productsQuery.Where(x => x.ParentId == null);
            }
            else
            {
                productsQuery = productsQuery.Where(x => x.ParentId == nodeid.Value);
            }

            var products = productsQuery.OrderBy(request.sidx + " " + request.sord)
                                        .Skip(pageIndex * pageSize)
                                        .Take(pageSize)
                                        .ToList();


            var newLevel = n_level == null ? 0 : n_level.Value + 1;
            var productsData = new JqGridData
            {
                Total = totalPages,
                Page = request.page,
                Records = totalRecords,
                Rows = (products.Select(comment => new JqGridRowData
                {
                    Id = comment.Id,
                    RowCells = new List<object> 
                               {
                                   comment.Id,
                                   comment.Body,
                                   comment.AddDateTime.ToPersianDate(),
                                   // اطلاعات خاص نمایش درختی به ترتیب
           newLevel,
           comment.ParentId == null ? "" : comment.ParentId.Value.ToString(CultureInfo.InvariantCulture),
           comment.IsNotExpandable,
           comment.IsExpanded
                               }
                })).ToList()
            };
            return Json(productsData, JsonRequestBehavior.AllowGet);
        }
    }
}

            $('#list').jqGrid({
                caption: "آزمایش سیزدهم",
                // .... مانند قبل
                treeGrid: true,
                treeGridModel: 'adjacency',
                ExpandColumn: '@(StronglyTyped.PropertyName<BlogComment>(x => x.Body))'
            }).jqGrid('gridResize', { minWidth: 400 });
        });

<AuthorizeView>
    <Authorized>
        <a href="Identity/Account/Logout">Logout</a>
    </Authorized>
    <NotAuthorized>
        <a href="Identity/Account/Register">Register</a>
        <a href="Identity/Account/Login">Login</a>
    </NotAuthorized>
</AuthorizeView>

InvalidOperationException: Authorization requires a cascading parameter of type Task<AuthenticationState>.
Consider using CascadingAuthenticationState to supply this.
Microsoft.AspNetCore.Components.Authorization.AuthorizeViewCore.OnParametersSetAsync()

<CascadingAuthenticationState>
    <Router AppAssembly="@typeof(Program).Assembly" PreferExactMatches="@true">
        <Found Context="routeData">
            <RouteView RouteData="@routeData" DefaultLayout="@typeof(MainLayout)" />
        </Found>
        <NotFound>
            <LayoutView Layout="@typeof(MainLayout)">
                <p>Sorry, there's nothing at this address.</p>
            </LayoutView>
        </NotFound>
    </Router>
</CascadingAuthenticationState>

@page
@using Microsoft.AspNetCore.Identity
@inject SignInManager<IdentityUser> SignInManager

@functions
{
    public async Task<IActionResult> OnGet()
    {
        if (SignInManager.IsSignedIn(User))
        {
            <p>You have successfully logged out of the application.</p>
            await SignInManager.SignOutAsync();
        }
        return Redirect("~/");
    }
}

<AuthorizeView>
    <Authorized>
        Hello, @context.User.Identity.Name
        <a href="Identity/Account/Logout">Logout</a>
    </Authorized>

@attribute [Authorize]

<CascadingAuthenticationState>
    <Router AppAssembly="@typeof(Program).Assembly" PreferExactMatches="@true">
        <Found Context="routeData">
            @*<RouteView RouteData="@routeData" DefaultLayout="@typeof(MainLayout)" />*@
            <AuthorizeRouteView RouteData="@routeData" DefaultLayout="@typeof(MainLayout)">
                <NotAuthorized>
                    <p>Sorry, you do not have access to this page</p>
                </NotAuthorized>
            </AuthorizeRouteView>
        </Found>
        <NotFound>
            <LayoutView Layout="@typeof(MainLayout)">
                <p>Sorry, there's nothing at this address.</p>
            </LayoutView>
        </NotFound>
    </Router>
</CascadingAuthenticationState>

<a rel="popover" 
               data-content="محتوایی برای نمایش" 
               data-original-title="عنوان" href="#">اطلاعات</a>

    <script type="text/javascript">
        $(document).ready(function () {
            $("[rel='popover']").popover({ placement: 'left' })
                            .click(function (e) { e.preventDefault(); });
        });
   </script>

@model Mvc4TwitterBootStrapTest.Models.User
@{
    ViewBag.Title = "Index";
}
@using (Html.BeginForm())
{
    @Html.ValidationSummary(true, null, new { @class = "alert alert-error alert-block" })

    <fieldset class="form-horizontal">
        <legend>تعریف کاربر جدید</legend>
        <div class="control-group">
            @Html.LabelFor(model => model.Name, new { @class = "control-label" })
            <div class="controls">
                @Html.EditorFor(model => model.Name)
                @*@Html.ValidationMessageFor(model => model.Name, null, new { @class = "help-inline" })*@
            </div>
        </div>
        <div class="control-group">
            @Html.LabelFor(model => model.LastName, new { @class = "control-label" })
            <div class="controls">
                @Html.EditorFor(model => model.LastName)
                @*@Html.ValidationMessageFor(model => model.LastName, null, new { @class = "help-inline" })*@
            </div>
        </div>
        <div class="form-actions">
            <button type="submit" class="btn btn-primary">
                ارسال</button>
        </div>
    </fieldset>
}
@section JavaScript
{
    <script type="text/javascript">
        $.validator.setDefaults({
            showErrors: function (errorMap, errorList) {
                this.defaultShowErrors();
                //اگر المانی معتبر است نیاز به نمایش پاپ اور ندارد
                $("." + this.settings.validClass).popover("destroy");
                //افزودن پاپ اورها
                for (var i = 0; i < errorList.length; i++) {
                    var error = errorList[i];
                    $(error.element).popover({ placement: 'left' })
                                    .attr("data-original-title", "خطای اعتبارسنجی")
                                    .attr("data-content", error.message);
                }
            },
            // همانند قبل برای رنگی کردن کل ردیف در صورت عدم اعتبار سنجی و برعکس
            highlight: function (element, errorClass, validClass) {
                if (element.type === 'radio') {
                    this.findByName(element.name).addClass(errorClass).removeClass(validClass);
                } else {
                    $(element).addClass(errorClass).removeClass(validClass);
                    $(element).closest('.control-group').removeClass('success').addClass('error');
                }
                $(element).trigger('highlited');
            },
            unhighlight: function (element, errorClass, validClass) {
                if (element.type === 'radio') {
                    this.findByName(element.name).removeClass(errorClass).addClass(validClass);
                } else {
                    $(element).removeClass(errorClass).addClass(validClass);
                    $(element).closest('.control-group').removeClass('error').addClass('success');
                }
                $(element).trigger('unhighlited');
            }
        });
        //برای حالت پست بک از سرور عمل می‌کند
        $(function () {
            $('form').each(function () {
                $(this).find('div.control-group').each(function () {
                    if ($(this).find('span.field-validation-error').length > 0) {
                        $(this).addClass('error');
                    }
                });
            });
        });
   </script>
}

<input class="text-box single-line" data-val="true" data-val-required="لطفا نام را تکمیل کنید"
 id="Name" name="Name" type="text" value="" />

<input class="text-box single-line input-validation-error" data-val="true" data-val-required="لطفا نام را تکمیل کنید"
 id="Name" name="Name" type="text" value="" 
data-original-title="خطای اعتبارسنجی" title="" data-content="لطفا نام را تکمیل کنید">

 @Html.TextBoxFor(x => x.Name, 
         new { data_content = "Name is required", 
               data_original_title = "Error", rel="popover" })