Grid rowdatabound event Find control ASP.NET C# - Creating control - enable or disable control

protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)

{

 Label lblDiscipline = ((Label)e.Row.FindControl("lblDiscipline"));

((DropDownList)e.Row.FindControl("ddlTitle")).Enabled = false;

}

Get date from datetime ASP.NET C#

 DateTime.ParseExact(DataBinder.Eval(e.Row.DataItem, "PresentInstitutePostingDate").ToString(), "mm/dd/yyyy", System.Globalization.CultureInfo.InvariantCulture).Date.ToString("d");

reference:- https://stackoverflow.com/questions/7740458/extract-the-date-part-from-datetime-in-c-sharp

Group by with max date ASP.NET C# LINQ - without model or entity

  var dt = GridView1.DataSource as DataTable;

                var a= dt.AsEnumerable().GroupBy(s => s.Field<string>("Discipline").ToString());

                

                

                //dt.DefaultView.Sort = sort;

                var final = dt.AsEnumerable().GroupBy(x => x.Field<string>("Discipline"), (key, g) => g.OrderByDescending(s => DateTime.ParseExact(s.Field<string>("PresentInstitutePostingDate") == ""?"01/01/1990": s.Field<string>("PresentInstitutePostingDate"), "mm/dd/yyyy", System.Globalization.CultureInfo.InvariantCulture)).First()).Select(t=> DateTime.ParseExact(t.Field<string>("PresentInstitutePostingDate") == "" ? "01/01/1990" : t.Field<string>("PresentInstitutePostingDate"), "mm/dd/yyyy", System.Globalization.CultureInfo.InvariantCulture));

                var tt = final.ToList();

                if (!string.IsNullOrEmpty(Convert.ToString(DataBinder.Eval(e.Row.DataItem, "PresentInstitutePostingDate"))))

                {

                    if (tt.Exists(o => o == DateTime.ParseExact(DataBinder.Eval(e.Row.DataItem, "PresentInstitutePostingDate").ToString(), "mm/dd/yyyy", System.Globalization.CultureInfo.InvariantCulture)))

                    {

                        e.Row.BackColor = System.Drawing.ColorTranslator.FromHtml("#0000ff");

                    }

                }

HTML Color codes

 https://htmlcolorcodes.com/

Grouping with Max Linq ASP.NET C# - without model or entity

  var dt = GridView1.DataSource as DataTable;

                var a= dt.AsEnumerable().GroupBy(s => s.Field<string>("Discipline").ToString());

                

                

                //dt.DefaultView.Sort = sort;

                var final = dt.AsEnumerable().GroupBy(x => x.Field<string>("Discipline"), (key, g) => g.OrderByDescending(s => s.Field<Int64>("ID")).First()).Select(t=>t.Field<Int64>("ID"));

                var tt = final.ToList();

                

                if(tt.Exists(o=> o == Convert.ToInt64(DataBinder.Eval(e.Row.DataItem, "ID"))))

                        {

                    e.Row.BackColor = System.Drawing.ColorTranslator.FromHtml("#0000ff");

                }

reference:-https://stackoverflow.com/questions/35170408/linq-how-to-get-the-max-id-with-a-group-by-clause