Delete User Requiring A Password

bool match = false;

public void delmethod()
{
if (connection.State != ConnectionState.Open)
                    {
                        connection.Open();
                    }
                    SqlCommand command = connection.CreateCommand();

                    command.CommandText = "SELECT * FROM YOURTABLE"; 
                    SqlDataReader dataread = command.ExecuteReader();
                    while (dataread.Read() && located != true)
                    {
                        if (textBox1.Text == dataread["PRECISEPASSWORD"].ToString())
                        {
                                match = true; 
                        }
                        else
                        {
                            match = false;
                        }
                            
                    }
                  
                }


       private void button1_Click(object sender, EventArgs e)
        {
            
            delmethod(); //calls for the delete method

            if (match == true) //registered user found
            {
            SqlConnection connection = new SqlConnection(ConnectionString.Conn);
            connection.Open();
            SqlCommand asd = connection.CreateCommand();
            asd.CommandText = "DELETE FROM YOUTRABLE WHERE Username ='" + YOURUSERNAME + "'"; 
            asd.ExecuteNonQuery();
            connection.Close();

            }