Notes

using System;
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Linq;
using System.Reflection.PortableExecutable;
using System.Text;
using System.Threading.Tasks;

namespace PrjrctExrcseTsk
{
internal class CorrectCrudOprtnUsnNdb
{
SqlConnection conn;


static void Main()
{


CorrectCrudOprtnUsnNdb scd = new CorrectCrudOprtnUsnNdb();
Console.WriteLine();
Console.WriteLine("Categories Before Insert");
Console.WriteLine("-----------------");

scd.ReadData();
//scd.Insertdata();
//Console.WriteLine();
//Console.WriteLine("Categories After Insert");
//Console.WriteLine("----------------------");
//scd.ReadData();


//scd.UpdateData();
//Console.WriteLine();
//Console.WriteLine("Categories After update");
//Console.WriteLine("------------------");

//scd.ReadData();


//scd.DeleteData();
//Console.WriteLine();
//Console.WriteLine("Categories After Delete");
//Console.WriteLine("------------------");

//scd.ReadData();

//use Scaller method
int numberOfRecords = scd.GetNumberOfRecords();
Console.WriteLine();
Console.WriteLine("Number of Records:{0}", numberOfRecords);





}
// public ReadData()
// {
// //conn = new SqlConnection("Data Source=(localdb)\MSSQLLocalDB;Initial Catalog=Northwind;Integrated Security=SSPI");
// string connectionString = "Data Source=(localdb)\MSSQLLocalDB;Initial Catalog=Northwind;" + "Integrated Security=true";

// string queryString = "SELECT ProductID,UnitPrice,ProductName from dbo.products WHERE UnitPrice > @pricePoint ORDER BY UnitPrice DESC;";

// //int paramValue = 5;
// using (SqlConnection connection = new SqlConnection(connectionString))
// {
// SqlCommand command = new SqlCommand(queryString, connection);
// //command.Parameters.AddWithValue("@pricePoint", paramValue);
// try
// {
// connection.Open();
// SqlDataReader reader = command.ExecuteReader();
// while (reader.Read())
// {
// Console.WriteLine("t{0}t{1}t{2}", reader[0], reader[1], reader[2]);

// }
// reader.Close();
// }
// catch (Exception ex)
// {
// Console.WriteLine(ex.Message);

// }
// Console.ReadLine();
// }


// }
//}











public int GetNumberOfRecords()
{
int count = -1;
try
{
conn.Open();

SqlCommand cmd = new SqlCommand(@"select count(*) from tblProducts", conn);
count = (int)cmd.ExecuteScalar();

}
finally
{
if (conn != null)
{
conn.Close();
}
}
return count;
}




//public void DeleteData()
//{
// try
// {
// conn.Open();
// string deleteString = @"delete from tblEmployee where Name='AJAY'";

// SqlCommand cmd = new SqlCommand();
// cmd.CommandText = deleteString;
// cmd.Connection = conn;
// cmd.ExecuteNonQuery();
// }
// finally
// {
// if (conn != null)
// {
// conn.Close();
// }
// }
//}













//public void UpdateData()
//{
// try
// {
// conn.Open();

// string updateString = @"update tblProducts set name='Arpit' where Name='Ajay'";

// SqlCommand cmd = new SqlCommand(updateString);
// cmd.Connection = conn;
// cmd.ExecuteNonQuery();
// }
// finally
// {
// if (conn != null)
// {
// conn.Close();
// }
// }
//}










//public void Insertdata()
//{
// try
// {
// conn.Open();
// string insertString = @"INSERT INTO tblProducts(name,description,quantity,unitPrice)values('Realme','Good With Performance',2,20000)";

// SqlCommand cmd = new SqlCommand(insertString, conn);
// cmd.ExecuteNonQuery();
// }
// finally
// {
// conn.Close();
// }
//}


public void ReadData()
{
conn = new SqlConnection("Data Source=(localdb)\MSSQLLocalDB;Initial Catalog=ExrcUsgDbDtnt;Integrated Security=SSPI");
SqlDataReader rdr = null;
try
{
conn.Open();
SqlCommand cmd = new SqlCommand("Select * from tblProducts", conn);
rdr = cmd.ExecuteReader();

while (rdr.Read())
{
Console.WriteLine(rdr[1]);
}
}
finally
{
if (rdr != null)
{
rdr.Close();
}
if (conn != null)
{
conn.Close();
}
}
}
}
}