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TADEventAlerter Class
published  TADEventAlerter Members  Example 1  Example 2  Classes  See Also  Send Feedback

The class is responsible for handling the database event notifications.

Group

Classes

Class Hierarchy
uADCompClient_TADEventAlerteruADCompClient_TADEventAlerter
File

uADCompClient

Links
published, TADEventAlerter Members, Example 1, Example 2, Classes, See Also
Description

Use the TADEventAlerter class to handle the database event notifications. 

The kind and general behavior of the events is DBMS specific. But TADEventAlerter provides unified way for handling them.

Syntax
TADEventAlerter = class(TADCustomEventAlerter);
See Also
Example 1
ADEventAlerter1.Options.Kind := 'DBMS_ALERT';
ADEventAlerter1.Names.Text := 'Customers';
ADEventAlerter1.Options.Synchronize := True;
ADEventAlerter1.Options.Timeout := 10000;
ADEventAlerter1.OnAlter := DoAlert;
ADEventAlerter1.OnTimeout := DoTimeout;
ADEventAlerter1.Active := True;
........

procedure TForm1.DoAlert(ASender: TADCustomEventAlerter;
  const AEventName: String; const AArgument: Variant);
begin
  if CompareText(AEventName, 'Customers') = 0 then
    qryCustomers.Refresh;
end;

procedure TForm1.DoTimeout(ASender: TObject);
begin
  qryCustomers.Refresh;
end;
Example 2

See the demo at: AnyDAC\Samples\Comp Layer\TADEventAlerter\Main

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