Solved

Reciving PSafeArray nad OleVariant Data from COM ....

Posted on 2001-09-05
5
1,601 Views
Last Modified: 2012-06-21
Hi Experts.
I'm building an OLE Automation Server that interfaces Excel XP :-(  
Anyway.
I Recieve/Send one type of data that I don't know how to handle :

var Strings : PSafeArray
========================

PSafeArray is a pointer to a SafeArray.
In this case it points to an array of Strings
(The VB code is [strings() As Variant])
The array dimensions are [0..1, 0..x] where x is
the number of items sent.
In one case I need to read the array, in the second I need
to write it.
I DONT KNOW WHERE TO START FROM

Any help on how to read and write this structure will be appreciated.

Best Regards
Marco
0
Comment
Question by:mgesiot
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
  • 2
5 Comments
 
LVL 14

Expert Comment

by:AvonWyss
ID: 6458507
Try this:

function SafeArrayToVariant(SaveArray: PSafeArray): OleVariant;
begin
     TVarData(Result).VType:=varArray;
     TVarData(Result).VArray:=PVarArray(SaveArray);
end;

[...]
var
     Strings: OleVariant;
     Temp: PSafeArray;
[...]
     {I assume that Temp holds the PSafeArray)
     Strings:=SafeArrayToVariant(Temp);
0
 
LVL 14

Expert Comment

by:AvonWyss
ID: 6458517
Btw. the other way around is like this:

function VariantToSafeArray(const Array: OleVariant): OleVariant;
begin
    Assert(TVarData(Arr).VType=varArray);
    Result:=PSafeArray(TVarData(Arr).VArray);
end;

And when it is in the Variant, you can just use it like a normal Pascal array...:

    Edit1.Text:=Strings[0];
0
 
LVL 14

Accepted Solution

by:
AvonWyss earned 300 total points
ID: 6458520
Sorry, should be:

function VariantToSafeArray(const Arr: OleVariant): PSafeArray;
0
 

Author Comment

by:mgesiot
ID: 6459549
Thanks!
Anyway I made it myself using
SAFEARREAYCREATE
SAFEARRAYGETDIM
SAFEARRAYGETUBOUND
SAFEARRAYPUTELEMENT
SAFEARRAYGETELEMENT

Api functions.
Now I wonder if I actually need all of this
or if the compiler takes charge of creating and
destroying the SafeArray.
I'll try your suggestions and let you know
within a couple of days.

Thanks again
Marco
0
 

Author Comment

by:mgesiot
ID: 6478778
Thanks a lot
0

Featured Post

Industry Leaders: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

The uses clause is one of those things that just tends to grow and grow. Most of the time this is in the main form, as it's from this form that all others are called. If you have a big application (including many forms), the uses clause in the in…
Creating an auto free TStringList The TStringList is a basic and frequently used object in Delphi. On many occasions, you may want to create a temporary list, process some items in the list and be done with the list. In such cases, you have to…
In an interesting question (https://www.experts-exchange.com/questions/29008360/) here at Experts Exchange, a member asked how to split a single image into multiple images. The primary usage for this is to place many photographs on a flatbed scanner…
This video shows how to use Hyena, from SystemTools Software, to update 100 user accounts from an external text file. View in 1080p for best video quality.

740 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question