Using GetParamValue and SetParamValue

rbuser

Hello All!

I am using v10.03 and I have a question about using the functions above.

Below is a block of code that I recently encountered. Within that block
of code, the two functions are used.

My question are, what exactly happens when GetParamValue and SetParamValue
is called? And, is it possible to use either of these functions to pass a
value in at runtime
to be operated upon, if this is not what is actually already happening with
either of the function calls?

Thanks in advance for any/all replies.

Everett
=======================================================================

{ TraConfigSettingFunction }
procedure TraConfigSettingFunction.ExecuteFunction(aParams: TraParamList);
var
sSettingName: String;
aResult : Boolean;
begin
try
aResult := False;
GetParamValue(0, sSettingName); //What does this do?
aResult:= (ConfigSettingsSingleton.Items.IndexOf(sSettingName) <> -1);
SetParamValue(1, aResult); //What does this do?
except
on E: Exception do begin
LogNTEventSilent(etError, ctErrors,
'An error occurred in Print Server Method "procedure
TraConfigSettingFunction.ExecuteFunction"' +
#13#10 + #13#10 +
E.Message);
end;
end;
end; {procedure, ExecuteFunction}

nicocizik

Hi Everett,

For future reference, it is best to post RAP questions in the RAP newsgroup.
This helps us provide a more accurate answer and a quicker response.

When creating a RAP passthru function you use the ExecuteFunction to
retrieve any parameters given by the code in RAP and set a return value to
the call if needed. The TraParamList holds these values. The first values
in the ParamList are the parameters defined in RAP (from the function call).
The last parameter is to be set inside the ExecuteFunction routine in Delphi
as a return value. Take a look at the passthru function below for a classic
example. As you can see the actuall signature of the function in RAP takes
a string parameter and returns a string parameter. In the ExecuteFuction
procedure, you can see that the first parameter is extracted using
GetParamValue, then processed in Delphi and then the return value is set
using the SetParamValue.

If you are looking to simply pass a value from Delphi to be used in RAP,
take a look at the Report.Parameters property in the RBuilder help.


{------------------------------------------------------------------------------}
{ TmyExtractFilePathFunction.GetSignature }

class function TmyExtractFilePathFunction.GetSignature: String;
begin
Result := 'function ExtractFilePath(const FileName: string): string;';
end; {class function GetSignature}

{------------------------------------------------------------------------------}
{ TmyExtractFilePathFunction.ExecuteFunction }

procedure TmyExtractFilePathFunction.ExecuteFunction(aParams: TraParamList);
var
lsResult: String;
lsString: String;
begin

GetParamValue(0, lsString);

lsResult := ExtractFilePath(lsString);

SetParamValue(1, lsResult);
end; {Procedure ExecuteFunction}

--
Regards,

Nico Cizik
Digital Metaphors
http://www.digital-metaphors.com

rbuser

Nico:

Thank you very much for your reply!

My apologies to all of the group for posting in the incorrect forum; I
overlooked it.

Nico, thanks for your feedback; that really does help a lot.

Regards,
Everett