private void ebtnDanhSachPhongBan_Click(object sender, EventArgs e)
 {
     if (dSDonVi == null || dSDonVi.IsDisposed)
     {
         dSDonVi = new FrmDSDonVi();
     }
     dSDonVi.MdiParent = this;
     dSDonVi.Show(dockPanelMain);
 }
 private void danhSáchHợpĐồngToolStripMenuItem_Click(object sender, EventArgs e)
 {
     if (dSDonVi == null || dSDonVi.IsDisposed)
     {
         dSDonVi = new FrmDSDonVi();
     }
     dSDonVi.MdiParent = this;
     dSDonVi.Show(dockPanelMain);
     this.Activate();
 }