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從DLL加載過程時，無論是動態加載還是靜態加載過程中遇到問題。當我把程序從dll傳遞給我的單元時，一切正常。當我試着使用DLL來做到這一點它給了我德爾福在嘗試從DLL加載過程時出錯
First chance exception at $00526399. Exception class $C0000005 with message 'access violation at 0x00526399: read of address 0x00000390'. Process Project1.exe (21988)
unit Unit1;
interface
uses
Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Vcl.ComCtrls,Unit2;
type
TForm1 = class(TForm)
ListView1: TListView;
Button1: TButton;
Button2: TButton;
Edit1: TEdit;
Edit2: TEdit;
Edit3: TEdit;
Edit4: TEdit;
Edit5: TEdit;
procedure FormCreate(Sender: TObject);
procedure FormClose(Sender: TObject; var Action: TCloseAction);
procedure Refresh;
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
type
plist = ^element;
element = record
artist,title,genre: string[20];
year,grade: integer;
wsk: plist;
end;
database = file of element;
var
base: database;
first: plist;
handler: HModule;
{$R *.dfm}
procedure TForm1.Refresh();
var
current: plist;
begin
ListView1.Clear;
current:= first;
while current<>nil do
begin
with ListView1.Items.Add do
begin
Caption:=current^.artist;
SubItems.Add(current^.title);
SubItems.Add(current^.genre);
SubItems.Add(IntToStr(current^.year));
SubItems.Add(IntToStr(current^.grade));
end;
current:=current^.wsk;
end;
end;
procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
var Save: procedure;
begin
handler:=LoadLibrary('lib.dll');
try
@Save:=GetProcAddress(handler, PChar(2));
if @Save = nil then raise Exception.Create('Load nie dziala');
Save();
finally
FreeLibrary(handler);
end;
end;
procedure TForm1.FormCreate(Sender: TObject);
var
Load: procedure;
begin
handler:=LoadLibrary('lib.dll');
try
@Load:=GetProcAddress(handler, PChar(1));
if @Load = nil then raise Exception.Create('Load nie dziala');
Load();
finally
FreeLibrary(handler);
end;
Refresh();
end;
procedure TForm1.Button1Click(Sender: TObject);
var
el: element;
Add: procedure(el:element);
begin
el.artist:=Edit1.Text;
el.title:=Edit2.Text;
el.genre:=Edit3.Text;
el.year:=StrToInt(Edit4.Text);
el.grade:=StrToInt(Edit5.Text);
handler:=LoadLibrary('lib.dll');
try
@Add:=GetProcAddress(handler, PChar(3));
if @Add = nil then raise Exception.Create('Load nie dziala');
Add(el);
finally
FreeLibrary(handler);
Refresh();
{Form2:=TForm2.Create(Form1);
Form2.ShowModal;
Form2.Free;}
end;
end;
end.
的DLL文件看起來是這樣的：
library lib;
{ Important note about DLL memory management: ShareMem must be the
first unit in your library's USES clause AND your project's (select
Project-View Source) USES clause if your DLL exports any procedures or
functions that pass strings as parameters or function results. This
applies to all strings passed to and from your DLL--even those that
are nested in records and classes. ShareMem is the interface unit to
the BORLNDMM.DLL shared memory manager, which must be deployed along
with your DLL. To avoid using BORLNDMM.DLL, pass string information
using PChar or ShortString parameters. }
uses
System.SysUtils,
System.Classes;
{$R *.res}
type plist = ^element;
element = record
artist,title,genre:string[20];
year,grade:integer;
wsk: plist;
end;
database = file of element;
var
first: plist;
base: database;
procedure add(el: element); stdcall;
var current,tmp: plist;
begin
New(current);
current^ := el;
current^.wsk := nil;
if first = nil then
begin
first:=current;
end else
begin
tmp:=first;
while tmp^.wsk<>nil do
begin
tmp:=tmp^.wsk;
end;
tmp^.wsk:=current;
end;
end;
procedure load();stdcall;
var
el: element;
i: integer;
begin
AssignFile(base, 'baza.dat');
if not FileExists('baza.dat') then
begin
Rewrite(base);
end else
begin
Reset(base);
for i := 0 to FileSize(base)-1 do
begin
read(base, el);
add(el);
end;
end;
CloseFile(base);
end;
procedure save();stdcall;
var
current: plist;
el: element;
begin
AssignFile(base, 'baza.dat');
Rewrite(base);
current:=first;
while current<>nil do
begin
el:=current^;
el.wsk:=nil;
write(base, el);
current:= current^.wsk;
end;
end;
exports
add index 1,
load index 2,
save index 3;
begin
end.
這也說明我的錯誤：
Expected ';' but received and identifier 'index' at line 91
但出口完成就像我在網上紅。