Applies to
TRPCBroker component
Declaration
property Connected: Boolean;
Description
This property connects your application to the
server:
It is not necessary for your application to manually establish a connection
to the server. This version of the Broker automatically connects and disconnects
from the server. When you invoke an RPC, if a
connection has not already been established, one will be established for you.
However, a user will not be able to run your RPC unless a context has been
created with the CreateContext method.
There
are other advantages to establishing a connection manually. You can check if a
connection is established, and branch accordingly depending on whether a
connection was established or not. One good place to do this is in your
application form's OnCreate event. For that event, you could include code like
the following:
try
RPCBroker1.Connected:=True;
except
On EBrokerError do
begin
ShowMessage('Connection to server could not be established!');
Application.Terminate;
end;
end;
This code sets the TRPCBroker component's
Connected property to True to establish a connection. If a Broker exception
(i.e., EBrokerError) was raised (in which case the
connection wasn't established), it provides a message to the user and calls the
Terminate method to exit.
To verify that your application is connected
to the server, check the value of the Connected property.
If a
connected TRPCBroker component is destroyed (when
the application is closed, for example), that component will first disconnect
from the server. However, for programming clarity, it is advisable to disconnect
your application from the server manually by setting the Connected property to
False.
If your application uses more than one Broker component, you
should be aware of the component's connect and
disconnect behavior.