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PrintSystemObject.Commit Method

Definition

When overridden in a derived class, writes any changes that your program has made to the object's properties to the actual software or hardware component that the object represents.

public:
 abstract void Commit();
public abstract void Commit ();
abstract member Commit : unit -> unit
Public MustOverride Sub Commit ()

Examples

The following example shows how to use this method (called on a PrintQueue object, which overrides the method from PrintSystemObject) as part of the process of merging print tickets.

/// <summary>
/// Changes the user-default PrintTicket setting of the specified print queue.
/// </summary>
/// <param name="queue">the printer whose user-default PrintTicket setting needs to be changed</param>
static private void ChangePrintTicketSetting(PrintQueue queue)
{
    //
    // Obtain the printer's PrintCapabilities so we can determine whether or not
    // duplexing printing is supported by the printer.
    //
    PrintCapabilities printcap = queue.GetPrintCapabilities();

    //
    // The printer's duplexing capability is returned as a read-only collection of duplexing options
    // that can be supported by the printer. If the collection returned contains the duplexing
    // option we want to set, it means the duplexing option we want to set is supported by the printer,
    // so we can make the user-default PrintTicket setting change.
    //
    if (printcap.DuplexingCapability.Contains(Duplexing.TwoSidedLongEdge))
    {
        //
        // To change the user-default PrintTicket, we can first create a delta PrintTicket with
        // the new duplexing setting.
        //
        PrintTicket deltaTicket = new PrintTicket();
        deltaTicket.Duplexing = Duplexing.TwoSidedLongEdge;

        //
        // Then merge the delta PrintTicket onto the printer's current user-default PrintTicket,
        // and validate the merged PrintTicket to get the new PrintTicket we want to set as the
        // printer's new user-default PrintTicket.
        //
        ValidationResult result = queue.MergeAndValidatePrintTicket(queue.UserPrintTicket, deltaTicket);

        //
        // The duplexing option we want to set could be constrained by other PrintTicket settings
        // or device settings. We can check the validated merged PrintTicket to see whether the
        // the validation process has kept the duplexing option we want to set unchanged.
        //
        if (result.ValidatedPrintTicket.Duplexing == Duplexing.TwoSidedLongEdge)
        {
            //
            // Set the printer's user-default PrintTicket and commit the set operation.
            //
            queue.UserPrintTicket = result.ValidatedPrintTicket;
            queue.Commit();
            Console.WriteLine("PrintTicket new duplexing setting is set on '{0}'.", queue.FullName);
        }
        else
        {
            //
            // The duplexing option we want to set has been changed by the validation process
            // when it was resolving setting constraints.
            //
            Console.WriteLine("PrintTicket new duplexing setting is constrained on '{0}'.", queue.FullName);
        }
    }
    else
    {
        //
        // If the printer doesn't support the duplexing option we want to set, skip it.
        //
        Console.WriteLine("PrintTicket new duplexing setting is not supported on '{0}'.", queue.FullName);
    }
}
''' <summary>
''' Changes the user-default PrintTicket setting of the specified print queue.
''' </summary>
''' <param name="queue">the printer whose user-default PrintTicket setting needs to be changed</param>
Private Shared Sub ChangePrintTicketSetting(ByVal queue As PrintQueue)
    '
    ' Obtain the printer's PrintCapabilities so we can determine whether or not
    ' duplexing printing is supported by the printer.
    '
    Dim printcap As PrintCapabilities = queue.GetPrintCapabilities()

    '
    ' The printer's duplexing capability is returned as a read-only collection of duplexing options
    ' that can be supported by the printer. If the collection returned contains the duplexing
    ' option we want to set, it means the duplexing option we want to set is supported by the printer,
    ' so we can make the user-default PrintTicket setting change.
    '
    If printcap.DuplexingCapability.Contains(Duplexing.TwoSidedLongEdge) Then
        '
        ' To change the user-default PrintTicket, we can first create a delta PrintTicket with
        ' the new duplexing setting.
        '
        Dim deltaTicket As New PrintTicket()
        deltaTicket.Duplexing = Duplexing.TwoSidedLongEdge

        '
        ' Then merge the delta PrintTicket onto the printer's current user-default PrintTicket,
        ' and validate the merged PrintTicket to get the new PrintTicket we want to set as the
        ' printer's new user-default PrintTicket.
        '
        Dim result As ValidationResult = queue.MergeAndValidatePrintTicket(queue.UserPrintTicket, deltaTicket)

        '
        ' The duplexing option we want to set could be constrained by other PrintTicket settings
        ' or device settings. We can check the validated merged PrintTicket to see whether the
        ' the validation process has kept the duplexing option we want to set unchanged.
        '
        If result.ValidatedPrintTicket.Duplexing = Duplexing.TwoSidedLongEdge Then
            '
            ' Set the printer's user-default PrintTicket and commit the set operation.
            '
            queue.UserPrintTicket = result.ValidatedPrintTicket
            queue.Commit()
            Console.WriteLine("PrintTicket new duplexing setting is set on '{0}'.", queue.FullName)
        Else
            '
            ' The duplexing option we want to set has been changed by the validation process
            ' when it was resolving setting constraints.
            '
            Console.WriteLine("PrintTicket new duplexing setting is constrained on '{0}'.", queue.FullName)
        End If
    Else
        '
        ' If the printer doesn't support the duplexing option we want to set, skip it.
        '
        Console.WriteLine("PrintTicket new duplexing setting is not supported on '{0}'.", queue.FullName)
    End If
End Sub

Remarks

For example, when overridden by the PrintServer class, Commit will write changes that are made to the PrintServer object's properties to the actual computer that the object represents.

Applies to

See also