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Problems loading a Delphi 7 .DLL into a Delphi Project...Error.

Hey there, I am having Problems Loading my dll into a delphi Project - "Application"...consisting of 1 form and a button, which onClick event should load  BudgetReport.dll which in turn should export the Procedure/Function/Routine to display a Report (QuickReport Object) on a Form - InspectionSelection.
Each time I try to run it, delphi gives me an Exception error..."Project CallingDLL.exe raised exception class EOleSysError with message 'CoInitialize has not been called'....."
Here follows the code...Can someone please help me...I've been struggling for 2 days now...and it feels like a waist.
I will greatly appreciate it.
Thank you.

library BudgetReport; // The DLL to be loaded.

uses
  SysUtils,
  Classes,
  BRCI in 'BRCI.pas' {frmBudgetReport};

Procedure ShowReport; export;
begin
      frmBudgetReport := TfrmBudgetReport.Create(nil);
  try
        frmBudgetReport.QuickRep1.Preview;
  finally
        frmBudgetReport.Free;
  end;
end;

exports ShowReport;
{$R *.res}
 
begin
end.

unit InspectionSelection; // The main Unit

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, Spin;

type
  TfrmInspection = class(TForm)
    btnReport: TButton;
    btnClose: TButton;
    procedure btnReportClick(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  frmInspection: TfrmInspection;

  Procedure ShowReport; external 'C:\Carab_Programming\DLL Reports\BudgetReport.dll';

implementation

//uses Math;

{$R *.dfm}

procedure TfrmInspection.btnReportClick(Sender: TObject);
var LibHandle : THandle;
    fShowReport : Procedure;
begin
  LibHandle := LoadLibrary('C:\Carab_Programming\DLL Reports\BudgetReport.dll');
  if LibHandle = 0 then
    raise Exception.Create('Unable to Load DLL...')
  else
  begin
    try @fShowReport := GetProcAddress(LibHandle, 'ShowReport');
      if @fShowReport <> nil then
        fShowReport;
    except
      on E: Exception do
        ShowMessage('Exception error: ' + E.Message);
    end;
  end;
  FreeLibrary(LibHandle);
end;

end.
0
theoscheepers
Asked:
theoscheepers
  • 3
  • 2
1 Solution
 
ziolkoCommented:
is this error thrown when loading dll or when executing ShowReport?

ziolko.
0
 
ziolkoCommented:
anyway try this:

library BudgetReport; // The DLL to be loaded.

uses
  SysUtils,
  Classes,
  ActiveX,
  BRCI in 'BRCI.pas' {frmBudgetReport};

Procedure ShowReport; export;
begin
      frmBudgetReport := TfrmBudgetReport.Create(nil);
  try
        frmBudgetReport.QuickRep1.Preview;
  finally
        frmBudgetReport.Free;
  end;
end;

exports ShowReport;
{$R *.res}
 
begin
  CoInitialize(nil);
end.

ziolko
0
 
theoscheepersAuthor Commented:
Hey there ziolko, thanx for responding so quick, I have done that, but now it gives me an error 'External exception error c0000029' and then another error '....could not read from memmory...' What do you think?
0
 
theoscheepersAuthor Commented:
Nope, I restarted Delphi and tried again and it still gives me the same error. The program stops at fShowReport on the OnClick event of btnProcess...when I do a step through(F7) using a breakpoint it stops there giving me that error too. Shouldn't I set Parameter / Project options setting to set the file output directory or host program for the dll? Or is that only when I want to run the app / dll from within Delphi? Thanx
0
 
theoscheepersAuthor Commented:
Thanx ziolko, you did have the right answer, I just didn't change my Host Program Directory from our server to my local machine...it works perfectly!!!!!! Thanx a mill.
0

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