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Reciving PSafeArray nad OleVariant Data from COM ....

Posted on 2001-09-05
5
Medium Priority
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1,671 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
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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 1200 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

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