Solved

Export Rec/Var from DLL

Posted on 1998-03-24
6
163 Views
Last Modified: 2010-04-06
I need data from a DLL (a Record and some Variables) in 4 units. I know how to export procedure and functions, but i can't access the record and the variables from these units.
0
Comment
Question by:omsec
  • 4
  • 2
6 Comments
 
LVL 4

Accepted Solution

by:
d003303 earned 30 total points
ID: 1360811
Yo,
all variables in a DLL are private to the DLL itself. To pass these variables between different modules (DLL/EXE, DLL/DLL) you need to use a procedural interface.

Slash/d003303
0
 
LVL 2

Author Comment

by:omsec
ID: 1360812
do u mean, i shall write a procedure that do assigns the variables with data (initialize) and then export the whole thing to the host-program ?
0
 
LVL 4

Expert Comment

by:d003303
ID: 1360813
Something like that :
library xyz

// stuff...

var MyVar : TMyStruct;

function GetMyVar: TMyStruct;
begin
  Result := MyVar;
end;

procedure SetMyVar(NewVar : TMyStruct);
begin
  MyVar := NewVar;
end;

// export these two

// or another way would be

var MyVar : TMyStruct
    MySecondVar : TAnotherStruct;

procedure GetMyVars(var FirstVar : TMyStruct; var SecondVar : TAnotherStruct);
begin
  FirstVar := MyVar;
  SecondVar := MySecondVar;
end;

procedure SetMyVars(FirstVar : TMyStruct; SecondVar : TAnotherStruct);
begin
  MyVar := FirstVar
  MySecondVar := SecondVar;
end;

// and export these two.

Slash/d003303
0
Use Case: Protecting a Hybrid Cloud Infrastructure

Microsoft Azure is rapidly becoming the norm in dynamic IT environments. This document describes the challenges that organizations face when protecting data in a hybrid cloud IT environment and presents a use case to demonstrate how Acronis Backup protects all data.

 
LVL 4

Expert Comment

by:d003303
ID: 1360814
To clarify, I assumed these functions are called fromout the host application.
0
 
LVL 2

Author Comment

by:omsec
ID: 1360815
yeah, i see what you mean there. but something makes that a lil difficultm, cos i have to export a record, well this isnt really the probrlem, but four of its fields are arrays. do ya want me do email you the dll-project ?
0
 
LVL 4

Expert Comment

by:d003303
ID: 1360816
If you declare the record you are passing in your DLL and EXE, it should not be a problem. Many Win32API-structures are nested structures, and the API calls are all DLL interfaced.
E.g. create a unit that only declares the types you are using in your DLL and EXE in its interface section, and place it in your DLLs and EXEs uses clause.

Slash/d003303
0

Featured Post

DevOps Toolchain Recommendations

Read this Gartner Research Note and discover how your IT organization can automate and optimize DevOps processes using a toolchain architecture.

Question has a verified solution.

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

Suggested Solutions

Have you ever had your Delphi form/application just hanging while waiting for data to load? This is the article to read if you want to learn some things about adding threads for data loading in the background. First, I'll setup a general applica…
Hello everybody This Article will show you how to validate number with TEdit control, What's the TEdit control? TEdit is a standard Windows edit control on a form, it allows to user to write, read and copy/paste single line of text. Usua…
This Micro Tutorial will give you a basic overview how to record your screen with Microsoft Expression Encoder. This program is still free and open for the public to download. This will be demonstrated using Microsoft Expression Encoder 4.
This tutorial gives a high-level tour of the interface of Marketo (a marketing automation tool to help businesses track and engage prospective customers and drive them to purchase). You will see the main areas including Marketing Activities, Design …

810 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