public static FRM_Calculo Instance() { if (instance == null) { instance = new FRM_Calculo(); } return(instance); }
private void mCalcular_Click(object sender, EventArgs e) { for (int intIndex = Application.OpenForms.Count - 1; intIndex > 0; intIndex--) { if (Application.OpenForms[intIndex] != this) { Application.OpenForms[intIndex].Close(); } } FRM_Calculo form_calculo = new FRM_Calculo(); form_calculo.MdiParent = this; form_calculo.Show(); }