Command Parameter : SqlParameter « ADO.Net « C# / CSharp Tutorial
- C# / CSharp Tutorial
- ADO.Net
- SqlParameter
using System;
using System.Data;
using System.Data.SqlClient;
class CommandParameters
{
static void Main()
{
string fname = "Z";
string lname = "Z";
SqlConnection conn = new SqlConnection(@"server = .\sqlexpress;integrated security = true;database = northwind");
string sqlqry = @"select count(*) from employees";
string sqlins = @"insert into employees(firstname,lastname)values(@fname, @lname)";
string sqldel = @"delete from employees where firstname = @fname and lastname = @lname";
SqlCommand cmdqry = new SqlCommand(sqlqry, conn);
SqlCommand cmdnon = new SqlCommand(sqlins, conn);
cmdnon.Prepare();
cmdnon.Parameters.Add("@fname", SqlDbType.NVarChar, 10);
cmdnon.Parameters.Add("@lname", SqlDbType.NVarChar, 20);
try
{
conn.Open();
Console.WriteLine("Before INSERT: Number of employees {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 employees {0}\n", cmdqry.ExecuteScalar());
cmdnon.CommandText = sqldel;
Console.WriteLine("Executing statement {0}", cmdnon.CommandText);
cmdnon.ExecuteNonQuery();
Console.WriteLine("After DELETE: Number of employees {0}\n", cmdqry.ExecuteScalar());
}
catch (SqlException ex)
{
Console.WriteLine(ex.ToString());
}
finally
{
conn.Close();
Console.WriteLine("Connection Closed.");
}
}
}