services.AddDbContext<BloggingContext>(
   options => options.UseSqlServer(connectionString));

services.AddDbContextPool<BloggingContext>(
   options => options.UseSqlServer(connectionString));

public class BloggingContext : DbContext
{
   public BloggingContext(DbContextOptions<BloggingContext> options) : base(options){}

        public static void RunWithoutContextPooling()
        {
            Console.WriteLine("\nRun Without ContextPooling");
            var serviceProvider = new ServiceCollection()
                .AddEntityFrameworkSqlServer()
                .AddDbContext<BloggingContext>(
                    c => c.UseSqlServer(@"Server=(localdb)\mssqllocaldb;Database=Demo.ContextPooling;Trusted_Connection=True;ConnectRetryCount=0;"))
                .BuildServiceProvider();

            new RunTests().Start(serviceProvider);
        }

        public static void RunWithContextPooling()
        {
            Console.WriteLine("\nRun With ContextPooling");
            var serviceProvider = new ServiceCollection()
                .AddEntityFrameworkSqlServer()
                .AddDbContextPool<BloggingContext>(
                    c => c.UseSqlServer(@"Server=(localdb)\mssqllocaldb;Database=Demo.ContextPooling;Trusted_Connection=True;ConnectRetryCount=0;"),
                    poolSize: 16)
                .BuildServiceProvider();

            new RunTests().Start(serviceProvider);
        }

Run Without ContextPooling
[10:49:30.728] Context creations: 637 | Requests per second: 597
[10:49:31.746] Context creations: 1069 | Requests per second: 1050
[10:49:32.765] Context creations: 1088 | Requests per second: 1067
[10:49:33.784] Context creations: 1139 | Requests per second: 1119
[10:49:34.802] Context creations: 1138 | Requests per second: 1117
[10:49:35.831] Context creations: 1153 | Requests per second: 1120
[10:49:36.845] Context creations: 1126 | Requests per second: 1111
[10:49:37.873] Context creations: 1014 | Requests per second: 987
[10:49:38.898] Context creations: 1139 | Requests per second: 1111
[10:49:39.918] Context creations: 1086 | Requests per second: 1065

Total context creations: 10592
Requests per second:     1034

Run With ContextPooling
[10:49:40.982] Context creations: 32 | Requests per second: 1388
[10:49:41.991] Context creations: 0 | Requests per second: 1691
[10:49:43.014] Context creations: 0 | Requests per second: 1684
[10:49:44.031] Context creations: 0 | Requests per second: 1702
[10:49:45.049] Context creations: 0 | Requests per second: 1694
[10:49:46.067] Context creations: 0 | Requests per second: 1401
[10:49:47.075] Context creations: 0 | Requests per second: 1510
[10:49:48.107] Context creations: 0 | Requests per second: 1669
[10:49:49.127] Context creations: 0 | Requests per second: 1679
[10:49:50.147] Context creations: 0 | Requests per second: 1688

Total context creations: 32
Requests per second:     1610

[Display(Name = "رایانامه")]
[Required(AllowEmptyStrings = false, ErrorMessage = "رایانامه خود را وارد کنید.")]
[RegularExpression("\\w+([-+.']\\w+)*@\\w+([-.]\\w+)*\\.\\w+([-.]\\w+)*", ErrorMessage = "نشانی رایانامه پذیرفتنی نمی‌باشد.")]
[ExistField(Action = "EmailExist", Namespace = "Parsnet.Controllers", Controller = "Account", ErrorMessage = "این رایانامه پیشتر به کار گرفته شده است.")]
        public string Email { get; set; }

@Html.TextBoxFor(m => m.Email, new { @class = "form-control en", placeholder = @Html.DisplayNameFor(m => m.Email) })

<input data-val="true" data-val-existfiledvalidator="این رایانامه پیشتر به کار گرفته شده است." data-val-existfiledvalidator-url="/account/emailexist" data-val-regex="نشانی رایانامه پذیرفتنی نمی‌باشد." data-val-regex-pattern="\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*" data-val-required="رایانامه خود را وارد کنید." id="Email" name="Email" placeholder="رایانامه" value="" type="text">

namespace Parsnet
{
     public static MvcHtmlString SpanFor<TModel, TProperty>(this HtmlHelper<TModel> htmlHelper, Expression<Func<TModel, TProperty>> expression, object htmlAttributes)
        {
            
            var sb = new StringBuilder();

            var span = new TagBuilder("span");

            var metadata = ModelMetadata.FromLambdaExpression<TModel, TProperty>(expression, htmlHelper.ViewData);
            var name = ExpressionHelper.GetExpressionText(expression);
            var fullName = htmlHelper.ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(name);
            var value = "";

            if (metadata.Model != null && metadata.Model.GetType() == typeof(List<IdentityProvider.IdentityRole>))
            {
                var modelList = (List<IdentityProvider.IdentityRole>)metadata.Model;
                value = String.Join("، ", modelList.Select(r => r.Name));
            }
            else
            {
                value = htmlHelper.FormatValue(metadata.Model, null);
            }

            span.MergeAttributes<string, object>(((IDictionary<string, object>)HtmlHelper.AnonymousObjectToHtmlAttributes(htmlAttributes)));

            var fieldName = fullName.Split('.')[1];
            span.MergeAttribute("data-name", fieldName, true);
            span.MergeAttributes<string, object>(htmlHelper.GetUnobtrusiveValidationAttributes(name, metadata));

            sb.Append(span.ToString(TagRenderMode.StartTag));
            sb.Append(value);
            sb.Append(span.ToString(TagRenderMode.EndTag));

            return new MvcHtmlString(sb.ToString());
        }
    }
}

var metadata = ModelMetadata.FromLambdaExpression<TModel, TProperty>(expression, htmlHelper.ViewData);

var name = ExpressionHelper.GetExpressionText(expression);
var fullName = htmlHelper.ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(name);

if (metadata.Model != null && metadata.Model.GetType() == typeof(List<IdentityProvider.IdentityRole>))
            {
                var modelList = (List<IdentityProvider.IdentityRole>)metadata.Model;
                value = String.Join("، ", modelList.Select(r => r.Name));
            }
            else
            {
                value = htmlHelper.FormatValue(metadata.Model, null);
            }

span.MergeAttributes<string, object>(((IDictionary<string, object>)HtmlHelper.AnonymousObjectToHtmlAttributes(htmlAttributes)));

 span.MergeAttributes<string, object>(htmlHelper.GetUnobtrusiveValidationAttributes(name, metadata));

@Html.SpanFor(m => m.Profile.Email, new { @class = "editor", data_type = "text" })

<span class="editor" data-name="Email" data-type="text" data-val="true" data-val-existfiledvalidator="این رایانامه پیشتر به کار گرفته شده است." data-val-existfiledvalidator-url="/account/emailexist" data-val-regex="نشانی رایانامه پذیرفتنی نمی‌باشد." data-val-regex-pattern="\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*" data-val-required="رایانامه خود را وارد کنید.">alireza_s_84@yahoo.com</span>

    public class User
    {
        public int Id { get; set; }
        public string Name { get; set; }

        public virtual ICollection<BlogPost> BlogPosts { get; set; }
    }

    public class BlogPost
    {
        public int Id { get; set; }
        public string Title { get; set; }
        public string Content { get; set; }

        [ForeignKey("UserId")]
        public virtual User User { get; set; }
        public int UserId { get; set; }
    }

 var data = context.BlogPosts.ToList();

 var data = context.BlogPosts.ToList();

 var list = context.BlogPosts.Select(x => x.Content).Skip(15).Take(15).ToList();

 foreach (var post in context.BlogPosts)
{
     Console.WriteLine(post.User.Name);
}

 foreach (var post in context.BlogPosts.Include(x=>x.User))

 var data = context.BlogPosts.ToList();

 var data = context.BlogPosts.AsNoTracking().Skip(15).Take(15).ToList();

        private void problem5MoreThan1ConnectionPerRequest() 
        {
            using (var context = new MyContext())
            {
                var count = context.BlogPosts.ToList();
            }
        }

DataContext = from user in context.Users
                      where user.Id>10
                      select user;

 var list = context.BlogPosts.Where(x => x.Content.Contains("test"))

        public static int FindDuplicateImagesCount(string pdfFileName)
        {
            int count = 0;
            var pdf = new PdfReader(pdfFileName);

            var md5 = new MD5CryptoServiceProvider();
            var enc = new UTF8Encoding();
            var imagesHashList = new List<string>();

            int intPageNum = pdf.NumberOfPages;
            for (int i = 1; i <= intPageNum; i++)
            {
                var page = pdf.GetPageN(i);
                var resources = PdfReader.GetPdfObject(page.Get(PdfName.RESOURCES)) as PdfDictionary;
                if (resources == null) continue;

                var xObject = PdfReader.GetPdfObject(resources.Get(PdfName.XOBJECT)) as PdfDictionary;
                if (xObject == null) continue;

                foreach (var name in xObject.Keys)
                {
                    var pdfObject = xObject.Get(name);
                    if (!pdfObject.IsIndirect()) continue;

                    var imgObject = PdfReader.GetPdfObject(pdfObject) as PdfDictionary;
                    if (imgObject == null) continue;

                    var subType = PdfReader.GetPdfObject(imgObject.Get(PdfName.SUBTYPE)) as PdfName;
                    if (subType == null) continue;

                    if (!PdfName.IMAGE.Equals(subType)) continue;

                    byte[] imageBytes = PdfReader.GetStreamBytesRaw((PRStream)imgObject);
                    var md5Hash = enc.GetString(md5.ComputeHash(imageBytes));

                    if (!imagesHashList.Contains(md5Hash))
                    {
                        imagesHashList.Add(md5Hash);
                    }
                    else
                    {
                        Console.WriteLine("Found duplicate image @page: {0}.", i);
                        count++;
                    }
                }
            }

            pdf.Close();
            return count;
        }

    public class PdfSmartCopy2 : PdfSmartCopy
    {
        public PdfSmartCopy2(Document document, Stream os)
            : base(document, os)
        { }

        /// <summary>
        /// This is a forgotten feature in iTextSharp 5.3.4. 
        /// Actually its PdfSmartCopy is useless without this!
        /// </summary>
        protected override PdfIndirectReference CopyIndirect(PRIndirectReference inp, bool keepStructure, bool directRootKids)
        {
            return base.CopyIndirect(inp);
        }
    }

        public static void RemoveDuplicateObjects(string inFile, string outFile)
        {
            var document = new Document();
            var copy = new PdfSmartCopy2(document, new FileStream(outFile, FileMode.Create));
            document.Open();

            var reader = new PdfReader(inFile);

            var n = reader.NumberOfPages;
            for (int page = 0; page < n; )
            {
                copy.AddPage(copy.GetImportedPage(reader, ++page));
            }
            copy.FreeReader(reader);            

            document.Close();
        }

        private static void CreateTestFile()
        {
            using (var pdfDoc = new Document(PageSize.A4))
            {
                var pdfWriter = PdfWriter.GetInstance(pdfDoc, new FileStream("Test.pdf", FileMode.Create));
                pdfDoc.Open();

                var table = new PdfPTable(new float[] { 1, 2 });
                table.AddCell(Image.GetInstance("01.png"));
                table.AddCell(Image.GetInstance("01.png"));
                pdfDoc.Add(table);
            }
        }

using System;
using iTextSharp.text;
using PdfRpt.Core.Contracts;
using PdfRpt.Core.Helper;
using PdfRpt.FluentInterface;

namespace PdfReportSamples.CustomCellTemplate
{
    public class CustomCellTemplatePdfReport
    {
        public IPdfReportData CreatePdfReport()
        {
            return new PdfReport().DocumentPreferences(doc =>
            {
                doc.RunDirection(PdfRunDirection.RightToLeft);
                doc.Orientation(PageOrientation.Portrait);
                doc.PageSize(PdfPageSize.A4);
                doc.DocumentMetadata(new DocumentMetadata { Author = "Vahid", Application = "PdfRpt", Keywords = "Test", Subject = "Test Rpt", Title = "Test" });
                doc.Compression(new CompressionSettings
                               {
                                   CompressionLevel = CompressionLevel.BestCompression,
                                   EnableCompression = true
                               });
            })
             .DefaultFonts(fonts =>
             {
                 fonts.Path(AppPath.ApplicationPath + "\\fonts\\irsans.ttf",
                            Environment.GetEnvironmentVariable("SystemRoot") + "\\fonts\\verdana.ttf");
             })
             .PagesFooter(footer =>
             {
                 footer.DefaultFooter(DateTime.Now.ToString("MM/dd/yyyy"));
             })
             .PagesHeader(header =>
             {
                 header.DefaultHeader(defaultHeader =>
                 {
                     defaultHeader.ImagePath(AppPath.ApplicationPath + "\\Images\\01.png");
                     defaultHeader.Message("گزارش جدید ما");
                 });
             })
             .MainTableTemplate(template =>
             {
                 template.BasicTemplate(BasicTemplate.SnowyPineTemplate);
             })
             .MainTablePreferences(table =>
             {
                 table.ColumnsWidthsType(TableColumnWidthType.Relative);
                 table.MultipleColumnsPerPage(new MultipleColumnsPerPage
                 {
                     ColumnsGap = 20,
                     ColumnsPerPage = 2,
                     ColumnsWidth = 250,
                     IsRightToLeft = true,
                     TopMargin = 7
                 });
             })
             .MainTableDataSource(dataSource =>
             {
                 var table = new System.Data.DataTable("لیست حقوق");
                 table.Columns.Add("شخص", typeof(string));
                 table.Columns.Add("ماه", typeof(int));
                 table.Columns.Add("مبلغ", typeof(decimal));

                 var rnd = new Random();
                 for (int i = 0; i < 200; i++)
                     table.Rows.Add("شخص " + i, rnd.Next(1, 12), rnd.Next(400, 2000));

                 dataSource.DataTable(table);
             })
             .MainTableEvents(events =>
             {
                 events.DataSourceIsEmpty(message: "There is no data available to display.");
                 events.CellCreated(args =>
                     {
                         //change the background color of the cell based on the value
                         if (args.RowType == RowType.DataTableRow && args.Cell.RowData.Value != null && args.Cell.RowData.Value is decimal)
                         {
                             if ((decimal)args.Cell.RowData.Value <= 1000)
                                 args.Cell.BasicProperties.BackgroundColor = BaseColor.CYAN;
                         }
                     });
             })
             .MainTableSummarySettings(summary =>
             {
                 summary.OverallSummarySettings("جمع کل");
                 summary.PageSummarySettings("جمع صفحه");
                 summary.PreviousPageSummarySettings("نقل از ستون قبل");
             })
             .MainTableColumns(columns =>
             {
                 columns.AddColumn(column =>
                 {
                     column.PropertyName("rowNo");
                     column.IsRowNumber(true);
                     column.CellsHorizontalAlignment(HorizontalAlignment.Center);
                     column.IsVisible(true);
                     column.Order(0);
                     column.Width(1);
                     column.HeaderCell("ردیف");
                 });

                 columns.AddColumn(column =>
                 {
                     column.PropertyName("شخص");
                     column.CellsHorizontalAlignment(HorizontalAlignment.Center);
                     column.IsVisible(true);
                     column.Order(1);
                     column.Width(3);
                     column.HeaderCell("شخص");
                     column.ColumnItemsTemplate(t => t.CustomTemplate(new MyCustomCellTemplate()));
                 });

                 columns.AddColumn(column =>
                 {
                     column.PropertyName("ماه");
                     column.CellsHorizontalAlignment(HorizontalAlignment.Center);
                     column.IsVisible(true);
                     column.Order(2);
                     column.Width(2);
                     column.HeaderCell("ماه");
                     column.ColumnItemsTemplate(template =>
                     {
                         template.TextBlock();
                         template.ConditionalFormatFormula(list =>
                         {
                             var cellValue = int.Parse(list.GetSafeStringValueOf("ماه", nullValue: "0"));
                             if (cellValue == 7)
                             {
                                 return new CellBasicProperties
                                 {
                                     PdfFontStyle = DocumentFontStyle.Bold | DocumentFontStyle.Underline,
                                     FontColor = new BaseColor(System.Drawing.Color.Brown),
                                     BackgroundColor = new BaseColor(System.Drawing.Color.Yellow)
                                 };
                             }
                             return new CellBasicProperties { PdfFontStyle = DocumentFontStyle.Normal };
                         });
                     });
                 });

                 columns.AddColumn(column =>
                 {
                     column.PropertyName("مبلغ");
                     column.CellsHorizontalAlignment(HorizontalAlignment.Center);
                     column.IsVisible(true);
                     column.Order(3);
                     column.Width(2);
                     column.HeaderCell("مبلغ");
                     column.ColumnItemsTemplate(template =>
                     {
                         template.TextBlock();
                         template.DisplayFormatFormula(obj => obj == null ? string.Empty : string.Format("{0:n0}", obj));
                     });
                     column.AggregateFunction(aggregateFunction =>
                     {
                         aggregateFunction.NumericAggregateFunction(AggregateFunction.Sum);
                         aggregateFunction.DisplayFormatFormula(obj => obj == null ? string.Empty : string.Format("{0:n0}", obj));
                     });
                 });
             })
             .Export(export =>
                 {
                     export.ToXml();
                     export.ToExcel();
                 })
             .Generate(data => data.AsPdfFile(AppPath.ApplicationPath + "\\Pdf\\RptDataTableSample.pdf"));
        }
    }
}

using System;
using System.Collections.Generic;
using iTextSharp.text;
using iTextSharp.text.pdf;
using PdfRpt.Core.Contracts;
using PdfRpt.Core.Helper;

namespace PdfReportSamples.CustomCellTemplate
{
    public class MyCustomCellTemplate : IColumnItemsTemplate
    {
        Random _rnd = new Random();

        public void CellRendered(PdfPCell cell, Rectangle position, PdfContentByte[] canvases, CellAttributes attributes)
        {
        }

        public CellBasicProperties BasicProperties { set; get; }
        public Func<IList<CellData>, CellBasicProperties> ConditionalFormatFormula { set; get; }

        public PdfPCell RenderingCell(CellAttributes attributes)
        {
            var pdfCell = new PdfPCell();
            var table = new PdfPTable(1) { RunDirection = PdfWriter.RUN_DIRECTION_RTL };

            var filePath = AppPath.ApplicationPath + "\\Images\\" + _rnd.Next(1, 5).ToString("00") + ".png";
            var photo = PdfImageHelper.GetITextSharpImageFromImageFile(filePath);
            table.AddCell(new PdfPCell(photo, fit: false)
            {
                Border = 0,                
                VerticalAlignment = Element.ALIGN_BOTTOM,
                HorizontalAlignment = Element.ALIGN_CENTER
            });

            var name = attributes.RowData.TableRowData.GetSafeStringValueOf("شخص");
            table.AddCell(new PdfPCell(attributes.BasicProperties.PdfFont.FontSelector.Process(name))
            {
                Border = 0,
                HorizontalAlignment = Element.ALIGN_CENTER
            });

            pdfCell.AddElement(table);

            return pdfCell;
        }
    }
}

events.CellCreated(args =>
    {
         //change the background color of the cell based on the value
         if (args.RowType == RowType.DataTableRow && args.Cell.RowData.Value != null && args.Cell.RowData.Value is decimal)
         {
              if ((decimal)args.Cell.RowData.Value <= 1000)
                   args.Cell.BasicProperties.BackgroundColor = BaseColor.CYAN;
          }
      });