Converting a PSafeArray into a Array of Double?

[kaywarner]

Hi All, thanks for reading the post.

In my latest project, I'm trying to access a Method in a type library that requires a PSafeArray as one of its arguments (via COM interface).

Thus far, I have loaded a text file into an Array of doubles but now I am unable to pass it to the method.

the function i'm using is as below:

Function TForm1.BeamTempratureCalc (Periods: Integer): Double;
var
COM_Method_Data: PSafeArray; //to be sent to the method
Tmp: TempCalc;

begin
COM_Method_Data:=Addr(TempArray); //TempArray is an array of double
COM_Method_Data:=SafeArrayCreateVector(vt_R8,0,Periods);
COM_Method_Data.pvdata:=@COM_Method_Data;
Tmp:=coTempCalc.create;
BeamTempratureCalc:=Tmp.RateOfChange(COM_Method_Data,Periods);

Does anyone have any experience or advice for this kind of problem?

many thanks, Kay

 

[DjangMan]

For one COM interface I work with it wants an array (not sure it is a PSafeArray) but here's the code.

var
    va: OLEVariant;
begin

 va := VarArrayCreate([0,5],varVariant); //array of variants
 va[0] := Detail.View;
 va[1] := EmptyParam;
 va[2] := DetailComment.View;
 va[3] := PaymentSchedule.View;
 va[4] := DetailComment.View;
 va[5] := HeaderOptFld.View;

 ComObject.Compose(va);

 

[kaywarner]

Thanks for that DjangMan, thats really great.

Am i correct in thinking that you populate a OLEVarient with the information (in my case that would be an array of doubles), then when you use;

ComObject.Compose(va)

that converts the OLEVarient into a PSafeArray?

thanks, Kay

 

[DjangMan]

No - the .Compose method is specific to the COM object that I'm using.