//Agregar button
private void button1_Click(object sender, EventArgs e)
{
this.Hide();
AgregarAsignatura agregar = new AgregarAsignatura();
agregar.Show();
}
//Editar button
private void button2_Click(object sender, EventArgs e)
{
this.Hide();
AgregarAsignatura agregar = new AgregarAsignatura();
agregar.editar = true;
agregar.materiaAEditar = new Materia();
agregar.materiaAEditar = materias.Find(x => x.materiaCodigo == dgvMaterias.Rows[index].Cells[1].Value.ToString() && x.materiaProfesor == dgvMaterias.Rows[index].Cells[3].Value.ToString());
agregar.Show();
}