Add parameters to the SqlCommand : SqlCommand : ADO.Net C# Examples

    
using  System;
using  System.Data;
using  System.Data.SqlClient;

class  MainClass
{
      static  void  Main()
      {
            string  fname  =  "Z";
            string  lname  =  "Z";

            SqlConnection  conn  =  new  SqlConnection("server=(local)\\SQLEXPRESS;database=MyDatabase;Integrated  Security=SSPI;");

            string  sqlqry  =  @"select  count(*)  from  employee";

            string  sqlins  =  @"insert  into  employee(firstname,lastname)values(@fname,  @lname)";

            string  sqldel  =  @"delete  from  employee  where  firstname  =  @fname  and  lastname  =  @lname";

            SqlCommand  cmdqry  =  new  SqlCommand(sqlqry,  conn);
            SqlCommand  cmdnon  =  new  SqlCommand(sqlins,  conn);

            cmdnon.Parameters.Add("@fname",  SqlDbType.NVarChar,  10);
            cmdnon.Parameters.Add("@lname",  SqlDbType.NVarChar,  20);

            try
            {
                  conn.Open();

                  Console.WriteLine("Before  INSERT:  Number  of  employee  {0}\n",  cmdqry.ExecuteScalar());

                  cmdnon.Parameters["@fname"].Value  =  fname;
                  cmdnon.Parameters["@lname"].Value  =  lname;
                  Console.WriteLine("Executing  statement  {0}",  cmdnon.CommandText);
                  cmdnon.ExecuteNonQuery();
                  Console.WriteLine("After  INSERT:  Number  of  employee  {0}\n",  cmdqry.ExecuteScalar());

                  cmdnon.CommandText  =  sqldel;
                  Console.WriteLine("Executing  statement  {0}",  cmdnon.CommandText);
                  cmdnon.ExecuteNonQuery();
                  Console.WriteLine("After  DELETE:  Number  of  employee  {0}\n",  cmdqry.ExecuteScalar());
            }
            catch  (SqlException  ex)
            {
                  Console.WriteLine(ex.ToString());
            }
            finally
            {
                  conn.Close();
                  Console.WriteLine("Connection  Closed.");
            }
      }
}