Beginner programmer on sending error messages I am looking to optimize one function that returns error messages to the user.

    /// &lt;summary&gt;
    /// Handles the Ouverture event of the PrescriptionVue control.
    /// &lt;/summary&gt;
    /// &lt;param name="sender"&gt;The source of the event.&lt;/param&gt;
    /// &lt;param name="e"&gt;The &lt;see cref="System.EventArgs"/&gt; instance containing the event data.&lt;/param&gt;
    private void PrescriptionVueOuverture(object sender, EventArgs e)
    {
        Message message = ServiceCouchePolygoneFacade.Instance.RecalculerSuperficiePolygone();
        Message message2 = ServicePrescriptionFacade.Instance.MettreAJourTablePrescription();
        if (message != null || message2 != null)
        {
            if (message != null)
            {
                this.prescriptionVue.AfficherMessage(message);
            }
            else
            {
                this.prescriptionVue.AfficherMessage(message2);
            }

            this.prescriptionVue.Fermer();
        }

        this.InitialiserVue();
    }


I have 2 service that conduct different manipulation and both of them returns an Object "Message" that are either gonna bu null or contain the error.

What im looking to optimize is the condition block in wich i look if either of those are null and if one isnt, wich one, so that i can send the one that contains the error.
one way to do it is to use coalesce : 

/// &lt;summary&gt;
/// Handles the Ouverture event of the PrescriptionVue control.
/// &lt;/summary&gt;
/// &lt;param name="sender"&gt;The source of the event.&lt;/param&gt;
/// &lt;param name="e"&gt;The &lt;see cref="System.EventArgs"/&gt; instance containing the event data.&lt;/param&gt;
private void PrescriptionVueOuverture(object sender, EventArgs e)
{       
    var message = ServiceCouchePolygoneFacade.Instance.RecalculerSuperficiePolygone() ?? ServicePrescriptionFacade.Instance.MettreAJourTablePrescription();

    if(message != null)
    {
        this.prescriptionVue.AfficherMessage(message);

        this.prescriptionVue.Fermer();
    }

    this.InitialiserVue();
}


the coalesce would evaluate the left-hand operand, if it's null, then it'll get the right-hand operand.