private void btnAdd_Click(object sender, EventArgs e)
        {
            if (projectId == 0)
            {
                MessageBox.Show("Plase select project name first");
            }
            else
            {
                ProjectProgrammerDAO projectProgrammerDAO = new ProjectProgrammerDAO();
                ProjectProgrammer    projectProgrammer    = new ProjectProgrammer
                {
                    ProjectId    = projectId,
                    ProgrammerId = programmerId
                };

                try
                {
                    projectProgrammerDAO.Insert(projectProgrammer);
                }
                catch (Exception ex)
                {
                    MessageBox.Show(ex.Message);
                }

                listBox1.Items.Clear();
                GetAllProgrammer();
            }
        }