string query = @"SELECT * FROM USER_PROFILE
              WHERE LOGIN_ID = '"+loginId+@"' AND PASSWORD = '"+password+@"'";

protected void btnSearch_Click(object sender, EventArgs e)
{
 String cmd = @"SELECT [CustomerID], [CompanyName], [ContactName]
  FROM [Customers] WHERE CompanyName ='" + txtCompanyName.Text
  + @"'";

 SqlDataSource1.SelectCommand = cmd;

 GridView1.Visible = true;
}

SqlCommand cmd = new SqlCommand("SELECT UserID FROM Users WHERE UserName=@UserName AND Password=@Password");
cmd.Parameters.Add(new SqlParameter("@UserName", System.Data.SqlDbType.NVarChar, 255, UserName));
cmd.Parameters.Add(new SqlParameter("@Password", System.Data.SqlDbType.NVarChar, 255, Password));
dr = cmd.ExecuteReader();
if (dr.Read()) userId = dr.GetInt32(dr.GetOrdinal("UserID"));

var products = from p in db.products
      where p.description.StartsWith(_txtSearch.Text)
      select new
      {
          p.description,
          p.price,
          p.stock

      };

exec sp_executesql N'SELECT [t0].[description], [t0].[price], [t0].[stock]
FROM [dbo].[products] AS [t0]
WHERE [t0].[description] LIKE @p0',N'@p0 varchar(5)',@p0='sony%'

 db.Log = Console.Out;

public bool Validate(string loginId, string password)
{
 DataClassesDataContext db = new DataClassesDataContext();

 var validUsers = from user in db.USER_PROFILEs
           where user.LOGIN_ID == loginId
           && user.PASSWORD == password
           select user;

 if (validUsers.Count() > 0) return true;
 else return false;
}

SELECT [t0].[LOGIN_ID], [t0].[PASSWORD]
FROM [dbo].[USER_PROFILE] AS [t0]
WHERE ([t0].[LOGIN_ID] = @p0) AND ([t0].[PASSWORD] = @p1)

string sql = "select * from Trade where DealMember='" + this.txtParams.Text + "'";
var trades = driveHax.ExecuteQuery<Trade>(sql);

IEnumerable<Customer> results = db.ExecuteQuery<Customer>(
 "SELECT contactname FROM customers WHERE city = {0}", "Tehran");

using Name = System.String;
using Greeting = System.String;
using PersonalizedGreeting = System.String;
using static System.Console; 
namespace Test
{
 private static void Main(string[] args)
        {

        Func<Greeting, Name, PersonalizedGreeting> greet
                = (gr, name) => $"{gr}, {name}";
            Name[] names = { "alireza1", "Alirea2" };
            foreach (var name in names)
            {
                WriteLine(greet("hello", name));
            }
// prints: Hello, alireza1
            // Hello, Alirea2
            
            ReadLine();
        }

}

public static int Fibonacci(int x)
{
    if (x <= 1)
          return 1;
    return Fibonacci(x - 1) + Fibonacci(x - 2);
}

using System;
using System.Collections.Generic;
using System.Numerics; //needs a ref. to this assembly

namespace Fibonaci
{
   public class CFibonacci
   {
       public static int Fibonacci(int x)
       {
           if (x <= 1)
               return 1;
           return Fibonacci(x - 1) + Fibonacci(x - 2);
       }

       public static IEnumerable<BigInteger> BigFib(Int64 toNumber)
       {
           BigInteger previous = 0;
           BigInteger current = 1;

           for (Int64 y = 1; y <= toNumber; y++)
           {
               var auxiliar = current;
               current += previous;
               previous = auxiliar;
               yield return current;
           }
       }
   }
}

using System;
using System.Linq;

namespace Fibonaci
{
   class Program
   {
       static void Main()
       {
           foreach (var i in CFibonacci.BigFib(10))
           {
               Console.WriteLine("{0}", i);
           }

           var num = 12000;
           var fib = CFibonacci.BigFib(num).Last();
           Console.WriteLine("fib({0})={1}", num, fib);

           Console.WriteLine("Press a key...");
           Console.ReadKey();
       }
   }
}

fib(12000)=514263424911336592579396579289954520826834443526829600435873863248622
65414020714013892551476261070010099275571144059579167356039437242089427136323689
02207956221569622791450891447905907668251232675988098246382902426783148546665404
47372384043164600945249911273857878346679362876357499204290285069442042444471200
52292329349103672302428662317285015525888210397583707071480178840772972692357054
71823998861896761687119434646250991702691100894769561810834542099577336821493905
41651658937860506067011215222435859797671748514023462634575877112541265857011723
31453990415231608729534781720381122965899871018532003735284559342372552627132300
63895825396012087948050855095233633638445668687440232926253620457459973889510838
23542785159371236389909470974738599166720611351903568781845409425624666559791912
02212289710838873334773835118391287956725504426150461421914844191810523257658770
99885492757927034409234340065928400769741802132203888929463702342324148343605275
28928280472094493359682662519127203581813404104542972181231076224891404730611459
03321942693225066038987483163709402601230467054944349111055850348779989058517069
96087626795709205215727843443054577680024507650678240240742421270422674907476927
22422733945450760323640619100021663675080870429299040891840880753646474330069332
72320218334582268219906763463261387161318500503970491314781100556494361063341371
43577787961183154125538371204296752028496084633103476783071177779604042581017888
28257784920659671082363171157289668904381254080676855815524987553372657063695970
39668109161449140707240711279859427919912443872405284305891366802954763421905970
15206311458187449420118838775707435857999310870199585760807680179258273461000460
97527064929564528474349547038178370043823628944670926601955537657427194815893365
88494863101667547896798728140224921584809355334379707156342620570496834086358692
30946467203330676206265047960072392991634456381998479411463182171816379650120684
35082399788137090460167819041845511951296934273988759169877839532492294430334328
46972905198131530224288922834125154211248159843609629469051889033085360540770480
25633451201705370447586177546577777759300410144166197439355903631773088812515215
09638377918595294747887970034209028019490210394392422302403687059119407005858379
52137098994457236290005745735420803758853723206992134642997705010940581386168427
47382973672816710014652632509888958851675894223117421829434728942878605569971512
65291783384910157203679779458354245579846973830472593370160977523707902575129803
072039857524154149354311250529579592001