private void FormLivro_FormClosing(object sender, FormClosingEventArgs e) { FormMDI fr = (FormMDI)this.MdiParent; fr.frLivro = null; }
private void FormProfessor_FormClosing(object sender, FormClosingEventArgs e) { FormMDI fr = (FormMDI)this.MdiParent; fr.frProfessor = null; }