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Unable to call export function from bpl

I am using Delphi XE, I have the following setup:

Both Mydll.dll and Package1.bpl (runtime package) contain Unit3.pas

unit Unit3;

interface

implementation

uses Dialogs;

procedure TestProc(const S: string); stdcall;
begin
  MessageDlg(S, mtInformation, [mbOK], 0);
end;

exports TestProc;

end.


Case 1:

procedure TestProc(const S: string); stdcall; external 'mydll.dll';

procedure TForm1.Button3Click(Sender: TObject);
begin
  TestProc('Button3');
end;


Case 2:

procedure TestProc(const S: string); stdcall; external 'Package1.bpl';

procedure TForm1.Button3Click(Sender: TObject);
begin
  TestProc('Button3');
end;


Case 3:

procedure TForm1.Button3Click(Sender: TObject);
var H: THandle;
    P: procedure(const S: string); stdcall;
begin
  H := LoadPackage('Package1.bpl');
  try
    @P := GetProcAddress(H, PChar('TestProc'));
    if Assigned(P) then
      P('Button3');
  finally
    UnloadPackage(H);
  end;
end;


Case 1 and Case 3 have passed , but Case 2 will increase access to the violation .


My question, as shown below, is

1. Case 2 not supported?
2. Except in case 3, is there anyway a call to TestProc from Package1.bpl similarly to Case1?

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2 answers

, 2 , LoadPackage, .

procedure TestProc(const S: string); stdcall;  external 'Package1.bpl';


var
  hPackage : Cardinal;

procedure TForm1.Button1Click(Sender: TObject);
begin
   TestProc('Button3');
end;


initialization
  hPackage := LoadPackage('Package1.bpl');
finalization
  if hPackage<>0 then 
  UnloadPackage(hPackage);
+3

2 Package1 ( Project Options\Packages\Runtime packages). (external ) , .

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