namespace jQueryMvcSample02.Models
{
    public class BlogPost
    {
        public int Id { set; get; }
        public string Title { set; get; }
        public string Body { set; get; }
    }
}

using System.Collections.Generic;
using System.Linq;
using jQueryMvcSample02.Models;

namespace jQueryMvcSample02.DataSource
{
    public static class BlogPostDataSource
    {
        private static IList<BlogPost> _cachedItems;
        /// <summary>
        /// با توجه به استاتیک بودن سازنده کلاس، تهیه کش، پیش از سایر فراخوانی‌ها صورت خواهد گرفت
        /// باید دقت داشت که این فقط یک مثال است و چنین کشی به معنای
        /// تهیه یک لیست برای تمام کاربران سایت است
        /// </summary>
        static BlogPostDataSource()
        {
            _cachedItems = createBlogPostsInMemoryDataSource();
        }

        /// <summary>
        /// هدف صرفا تهیه یک منبع داده آزمایشی ساده تشکیل شده در حافظه است
        /// </summary>        
        private static IList<BlogPost> createBlogPostsInMemoryDataSource()
        {
            var results = new List<BlogPost>();
            for (int i = 1; i < 30; i++)
            {
                results.Add(new BlogPost { Id = i, Title = "عنوان " + i, Body = "متن ... متن ... متن " + i });
            }
            return results;
        }

        /// <summary>
        /// پارامترهای شماره صفحه و تعداد رکورد به ازای یک صفحه برای صفحه بندی نیاز هستند
        /// شماره صفحه از یک شروع می‌شود
        /// </summary>
        public static IList<BlogPost> GetLatestBlogPosts(int pageNumber, int recordsPerPage = 4)
        {
            var skipRecords = pageNumber * recordsPerPage;
            return _cachedItems
                        .OrderByDescending(x => x.Id)
                        .Skip(skipRecords)
                        .Take(recordsPerPage)
                        .ToList();
        }
    }
}

using System.Linq;
using System.Web.Mvc;
using System.Web.UI;
using jQueryMvcSample02.DataSource;
using jQueryMvcSample02.Security;

namespace jQueryMvcSample02.Controllers
{
    public class HomeController : Controller
    {
        [HttpGet]
        public ActionResult Index()
        {
            //آغاز کار با صفحه صفر است
            var list = BlogPostDataSource.GetLatestBlogPosts(pageNumber: 0);
            return View(list); //نمایش ابتدایی صفحه
        }

        [HttpPost]
        [AjaxOnly]
        [OutputCache(Location = OutputCacheLocation.None, NoStore = true)]
        public virtual ActionResult PagedIndex(int? page)
        {
            var pageNumber = page ?? 0;
            var list = BlogPostDataSource.GetLatestBlogPosts(pageNumber);
            if (list == null || !list.Any())
                return Content("no-more-info"); //این شرط ما است برای نمایش عدم یافتن رکوردها

            return PartialView("_ItemsList", list);
        }

        [HttpGet]
        public ActionResult Post(int? id)
        {
            if (id == null)
                return Redirect("/");

            //todo: show the content here
            return Content("Post " + id.Value);
        }
    }
}

@model IList<jQueryMvcSample02.Models.BlogPost>
<ul>
    @foreach (var item in Model)
    {
        <li>
            <h5>
                @Html.ActionLink(linkText: item.Title,
                                 actionName: "Post",
                                 controllerName: "Home",
                                 routeValues: new  { id = item.Id },
                                 htmlAttributes: null)
            </h5>
            @item.Body
        </li>
    }
</ul>

@model IList<jQueryMvcSample02.Models.BlogPost>
@{
    ViewBag.Title = "Index";
    var loadInfoUrl = Url.Action(actionName: "PagedIndex", controllerName: "Home");
}
<h2>
    اسکرول نامحدود</h2>
@{ Html.RenderPartial("_ItemsList", Model); }
<div id="MoreInfoDiv">
</div>
<div align="center" style="margin-bottom: 9px;">
    <span id="moreInfoButton" style="width: 90%;" class="btn btn-info">بیشتر</span>
</div>
<div id="ProgressDiv" align="center" style="display: none">
    <br />
    <img src="@Url.Content("~/Content/images/loadingAnimation.gif")" alt="loading..."  />
</div>
@section JavaScript
{
    <script type="text/javascript">
        $(document).ready(function () {
            $("#moreInfoButton").InfiniteScroll({
                moreInfoDiv: '#MoreInfoDiv',
                progressDiv: '#ProgressDiv',
                loadInfoUrl: '@loadInfoUrl',
                loginUrl: '/login',
                errorHandler: function () {
                    alert('خطایی رخ داده است');
                },
                completeHandler: function () {
                    // اگر قرار است روی اطلاعات نمایش داده شده پردازش ثانوی صورت گیرد
                },
                noMoreInfoHandler: function () {
                    alert('اطلاعات بیشتری یافت نشد');
                }
            });
        });
    </script>
}

// <![CDATA[
(function ($) {
    $.fn.InfiniteScroll = function (options) {
        var defaults = {
            moreInfoDiv: '#MoreInfoDiv',
            progressDiv: '#Progress',
            loadInfoUrl: '/',
            loginUrl: '/login',
            errorHandler: null,
            completeHandler: null,
            noMoreInfoHandler: null
        };
        var options = $.extend(defaults, options);

        var showProgress = function () {
            $(options.progressDiv).css("display", "block");
        }

        var hideProgress = function () {
            $(options.progressDiv).css("display", "none");
        }       

        return this.each(function () {
            var moreInfoButton = $(this);
            var page = 1;
            $(moreInfoButton).click(function (event) {
                showProgress();
                $.ajax({
                    type: "POST",
                    url: options.loadInfoUrl,
                    data: JSON.stringify({ page: page }),
                    contentType: "application/json; charset=utf-8",
                    dataType: "json",
                    complete: function (xhr, status) {
                        var data = xhr.responseText;
                        if (xhr.status == 403) {
                            window.location = options.loginUrl;
                        }
                        else if (status === 'error' || !data) {
                            if (options.errorHandler)
                                options.errorHandler(this);
                        }
                        else {
                            if (data == "no-more-info") {
                                if (options.noMoreInfoHandler)
                                    options.noMoreInfoHandler(this);
                            }
                            else {
                                var $boxes = $(data);
                                $(options.moreInfoDiv).append($boxes);
                            }
                            page++;
                        }
                        hideProgress();
                        if (options.completeHandler)
                            options.completeHandler(this);
                    }
                });
            });
        });
    };
})(jQuery);
// ]]>

using FluentValidationSample.Models;
using Microsoft.AspNetCore.Mvc;

namespace FluentValidationSample.Web.Controllers
{
    public class HomeController : Controller
    {
        public IActionResult Index()
        {
            return View();
        }

        [HttpPost]
        public IActionResult RegisterValidateManually(RegisterModel model)
        {
            var validator = new RegisterModelValidator();
            var validationResult = validator.Validate(model);
            if (!validationResult.IsValid)
            {
                return BadRequest(validationResult.Errors[0].ErrorMessage);
            }

            // TODO: Save the model

            return Ok();
        }
    }
}

public IActionResult RegisterValidateManually(RegisterModel model)
{
    var validator = new RegisterModelValidator();
    var validationResult = validator.Validate(model);
    if (!validationResult.IsValid)
    {
       validationResult.AddToModelState(ModelState, null);
       return BadRequest(ModelState);
    }

    // TODO: Save the model

    return Ok();
}

namespace FluentValidationSample.Web
{
    public class Startup
    {
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddTransient<IValidator<RegisterModel>, RegisterModelValidator>();
            services.AddControllersWithViews();
        }

namespace FluentValidationSample.Web.Controllers
{
    public class HomeController : Controller
    {
        private readonly IValidator<RegisterModel> _registerModelValidator;

        public HomeController(IValidator<RegisterModel> registerModelValidator)
        {
            _registerModelValidator = registerModelValidator;
        }

        [HttpPost]
        public IActionResult RegisterValidatorInjection(RegisterModel model)
        {
            var validationResult = _registerModelValidator.Validate(model);
            if (!validationResult.IsValid)
            {
                return BadRequest(validationResult.Errors[0].ErrorMessage);
            }

            // TODO: Save the model

            return Ok();
        }
    }
}

namespace FluentValidationSample.Web
{
    public class Startup
    {
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddTransient<IValidator<RegisterModel>, RegisterModelValidator>();
            services.AddControllersWithViews().AddFluentValidation();
        }

namespace FluentValidationSample.Web.Controllers
{
    public class HomeController : Controller
    {
        [HttpPost]
        public IActionResult RegisterValidatorAutomatically(RegisterModel model)
        {
            if (!ModelState.IsValid)
            {
                // re-render the view when validation failed.
                return View(model);
            }

            // TODO: Save the model

            return Ok();
        }
    }
}

namespace FluentValidationSample.Web.Controllers
{
    [Route("[controller]")]
    [ApiController]
    public class HomeController : Controller
    {
        [HttpPost]
        public IActionResult RegisterValidatorAutomatically(RegisterModel model)
        {
            // TODO: Save the model

            return Ok();
        }
    }
}

{
    "type": "https://tools.ietf.org/html/rfc7231#section-6.5.1",
    "title": "One or more validation errors occurred.",
    "status": 400,
    "traceId": "|84df05e2-41e0d4841bb61293.",
    "errors": {
        "FirstName": [
            "'First Name' must not be empty."
        ]
    }
}

        public void ConfigureServices(IServiceCollection services)
        {
            // ...

            // override modelstate
            services.Configure<ApiBehaviorOptions>(options =>
            {
                options.InvalidModelStateResponseFactory = context =>
                {
                    var errors = context.ModelState.Values.SelectMany(x => x.Errors.Select(p => p.ErrorMessage)).ToList();
                    return new BadRequestObjectResult(new
                    {
                        Code = "00009",
                        Message = "Validation errors",
                        Errors = errors
                    });
                };
            });
        }

namespace FluentValidationSample.Web
{
    public class Startup
    {
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddControllersWithViews().AddFluentValidation(
                fv => fv.RegisterValidatorsFromAssemblyContaining<RegisterModelValidator>()
            );
        }

public void ConfigureServices(IServiceCollection services)
{
    services.AddControllersWithViews().AddFluentValidation(
       fv =>
       {
           fv.RegisterValidatorsFromAssemblyContaining<RegisterModelValidator>();
           fv.RunDefaultMvcValidationAfterFluentValidationExecutes = false;
       }
    );
}