The following public unit use on the DLL project exactly? If it is, when the build is also on the DLL file? To use this DLL program also USES the public unit, is to copy a common element in the development of the program directory? So there is a DLL, the program of a folder, and two public unit file,,,, so do you,,,,
Screenshots are as follows:

The code is as follows:
With Delphi wrapper class to DLL:

A common unit:

 
The unit ITest; 

Interface 

Type 
IT=interface 
The function get string: a string; 
Procedure ShowMsg (p: PChar); 
Procedure of Msg. 
end; 

Implementation 

End. 

Class unit, the write inside the DLL:

 unit UTest; 

Interface 

USES the 
SysUtils, 
Windows, 
ITest; 

Type 
TTest=class (TInterfacedObject, IT) 
Private 
I: Integer; 
Protected 

Public 
The constructor Create;//override. 
The destructor Destroy; Override. 
The function get string: a string; 
Procedure ShowMsg (p: PChar); 
Procedure of Msg. 
Published 

end; 

Implementation 

The constructor TTest. Create; 
The begin 
I:=0; 
end; 

Destructor TTest. Destroy; 
The begin 
Inherited; 
end; 

The function TTest. Get string: a string; 
The begin 
Result:='Test string'; 
end; 

Procedure TTest. ShowMsg (p: PChar); 
The begin 
MessageBox (0, p, "Test", MB_OK); 
end; 

Procedure TTest. Msg; 
The begin 
Inc (I); 
MessageBox (0, 'Test MessageBox', PChar (IntToStr (I)), MB_OK); 
end; 

End. 

DLL PRJ:

 library Test; 

USES the 
SysUtils, 
Classes, 
ITest in 'ITest. Pas, 
UTest 'in UTest. Pas'; 

{$R *. Res} 

The function TestCreate: IT; Stdcall; 
The begin 
Result:=TTest. Create; 
end; 

Exports 
TestCreate;//use the initialization 

The begin 
End. 

DLL part that's it, calls to EXE parts:

 USES 
ITest;//reference units 

The function TestCreate: IT; Stdcall; External 'Test. DLL' name 'TestCreate';//reference DLL function 

//declare as test 
Private 
AA: IT; 
BB: IT; 

Procedure TForm1. FormCreate (Sender: TObject); 
The begin 
AA:=TestCreate; 
BB:=TestCreate; 
end; 

Procedure TForm1. Button1Click (Sender: TObject); 
The begin 
For the Caption:=AA. Get string; 
end; 

Procedure TForm1. Button2Click (Sender: TObject); 
The begin 
AA. ShowMsg (' 123 ABC "); 
end; 

Procedure TForm1. Button3Click (Sender: TObject); 
The begin 
AA. Msg; 
end; 

Procedure TForm1. Button4Click (Sender: TObject); 
The begin 
BB. Msg; 
end; 

CodePudding user response:

Should have, put a DLL and procedures,

CodePudding user response:

DLLS are not Shared communication parameters, free will, of course, the
But a better approach is to solve the Shared parameters, so you don't put,