private void button1_Click(object sender, EventArgs e)
	{
          //create your connection object
	SqlConnection connection = new SqlConnection("Data Source=(local);Initial Catalog=Northwind;Integrated Security=SSPI");
	//create your command object
	SqlCommand command = connection.CreateCommand()
        //tell the compiler that it is a text command not stored procedure
        command.CommandType = CommandType.Text;
         //tell it what the INSERT statement is
         command.CommandText = "INSERT INTO Customers ([Customer ID]) VALUES (cid)";
                        
                //open your connection - wrap DB calls in try,catch,finally blocks to catch any exceptions
                  try{
                        connection.Open();
                        //execute your Insert statement
                       command.ExecuteNonQuery();
                       }
               catch{
                       //catch your exceptions here
                       }
               //finally always executes - so close your connection here
              finally{
                   //always close connection
                        connection.Close();
                        }

		}