private void btnNovo_Click(object sender, EventArgs e)
 {
     using (var f = new FrmCadAluno())
     {
         f.ShowDialog();
     }
 }
 private void lstAlunos_MouseDoubleClick(object sender, MouseEventArgs e)
 {
     if (lstAlunos.SelectedItems.Count > 0)
     {
         var aluno = (Aluno)lstAlunos.SelectedItems[0].Tag;
         using (var f = new FrmCadAluno())
         {
             f.Edicao = aluno;
             f.ShowDialog();
         }
     }
 }