//sifremi unuttum  
          private void sifrekurtarmabuton_Click(object sender, EventArgs e) 
          { 
              if (txtsifreunut.Text != "") 
              { 
              SqlConnection conn = new SqlConnection("Data Source= localhost\\Sqlexpress; Initial Catalog=ARTELLADB; User Id=sa; password=1234;"); 
              conn.Open(); 
              SqlCommand kmt = new SqlCommand ("select sifre from kadivesifre where kadi = '@kadi'", conn); 
              kmt.Parameters.AddWithValue("@kadi",txtsifreunut.Text); 
              kmt.ExecuteNonQuery(); 
              SqlDataReader reader = kmt.ExecuteReader(); 
                  while (reader.Read()) 
                  { 
                      //textBox1.Clear(); 
                      textBox1.Text = reader["sifre"].ToString(); 
                       
                  } 
                  conn.Close(); 
                   } 
              else 
              { 
                  MessageBox.Show("Boş Geçilemez!", "Uyarı", MessageBoxButtons.OK, MessageBoxIcon.Error); 
              } 
          }