I have this DLL:
library WEB;
{ 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
ShareMem, SysUtils, Variants, Classes, System.Net.URLClient,
System.Net.HttpClient, System.Net.HttpClientComponent, StrUtils;
const
BrowserAgent: Array[0..1] of String = ( // Add as many as you wish
'Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Firefox/102.0',
'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.102 Safari/537.36 Edge/18.19582'
);
var
NetHTTPClient1: TNetHTTPClient;
theResponse: TStream;
theHeader: TNetHeaders;
HeaderArray: TStrings;
DummyValue: String;
{$R *.res}
function Split(Delimiter: Char; Str: string): TStrings;
var
ListOfStrings: TStringList;
begin
ListOfStrings := TStringList.Create;
ListOfStrings.Delimiter := Delimiter;
ListOfStrings.StrictDelimiter := True; // Requires D2006 or newer.
ListOfStrings.DelimitedText := Str;
Result := ListOfStrings;
end;
function GetHTTP(theURL,theHeaders, theOptions: PChar): PChar; {$ifdef win32} Stdcall;{$endif} Export;
var
I: Integer;
begin
if theURL <> '' then
begin
try
theHeader := TNetHeaders.Create();
theResponse := TStream.Create;
NetHTTPClient1 := TNetHTTPClient.Create(nil);
NetHTTPClient1.AcceptCharSet := 'UTF-8';
NetHTTPClient1.UserAgent := BrowserAgent[Random(2)];
try
if theHeaders <> '' then
begin
HeaderArray := Split('|',String(theHeaders));
for I := 0 to HeaderArray.Count - 1 do
begin
theHeader[I].Value := HeaderArray[I];
end;
end;
if UpperCase(theOptions) = 'YES' then
begin
DummyValue := PChar(NetHTTPClient1.Options(String(theURL),theResponse,theHeader).StatusText);
end;
Result := PChar(NetHTTPClient1.Get(String(theURL),theResponse, theHeader).ContentAsString());
except
on E : Exception do
Result := PChar('<html><head><title>Error page - '+E.ClassName+'</title></head>'+
'<body bgcolor="#ffffff" leftmargin="0" topmargin="0" '+
'marginwidth="0" marginheight="0"><table width="75%" '+
'border="0" cellpadding="50" cellspacing="0"><tr>'+
'<td><h3>Request error - '+E.ClassName+'</h3><p>The page you requested could '+
'not be found - due to an error.</p><p>This may has '+
'been caused by the following scenario:</p><ul><li>'+
'<p>'+E.Message+'.</p></li></ul>'+
'<p>Apology for the inconvenience.</p></td> </tr>'+
'</table></body></html>');
end;
finally
theResponse.Free;
theHeader := nil;
NetHTTPClient1.Free;
end;
end
else
begin
Result := PChar('<html><head><title>400 Error</title></head>'+
'<body bgcolor="#ffffff" leftmargin="0" topmargin="0" '+
'marginwidth="0" marginheight="0"><table width="75%" '+
'border="0" cellpadding="50" cellspacing="0"><tr>'+
'<td><h3>Bad Request</h3><p>The page you requested could '+
'not be found - due to a 400 error.</p><p>This may have '+
'been caused by the following scenarios:</p><ul><li>'+
'<p>You may have typed the address wrong</p></li><li>'+
'<p> We may have moved the page, created a bad link or '+
'be experiencing temporary problems.</p></li></ul>'+
'<p>Apology for the inconvenience.</p></td> </tr>'+
'</table></body></html>');
end;
end;
function PostHTTP(theURL,PostData,theHeaders, theOptions: PChar): PChar; {$ifdef win32} Stdcall;{$endif} Export;
var
I: Integer;
begin
if theURL <> '' then
begin
try
theHeader := TNetHeaders.Create();
theResponse := TStream.Create;
NetHTTPClient1 := TNetHTTPClient.Create(nil);
NetHTTPClient1.AcceptCharSet := 'UTF-8';
NetHTTPClient1.UserAgent := BrowserAgent[Random(2)];
try
if theHeaders <> '' then
begin
HeaderArray := Split('|',String(theHeaders));
for I := 0 to HeaderArray.Count - 1 do
begin
theHeader[I].Value := HeaderArray[I];
end;
end;
if UpperCase(theOptions) = 'YES' then
begin
DummyValue := PChar(NetHTTPClient1.Options(String(theURL),theResponse,theHeader).StatusText);
end;
Result := PChar(NetHTTPClient1.Post(String(theURL),String(PostData),theResponse, theHeader).ContentAsString());
except
on E : Exception do
Result := PChar('<html><head><title>Error page - '+E.ClassName+'</title></head>'+
'<body bgcolor="#ffffff" leftmargin="0" topmargin="0" '+
'marginwidth="0" marginheight="0"><table width="75%" '+
'border="0" cellpadding="50" cellspacing="0"><tr>'+
'<td><h3>Request error - '+E.ClassName+'</h3><p>The page you requested could '+
'not be found - due to an error.</p><p>This may has '+
'been caused by the following scenario:</p><ul><li>'+
'<p>'+E.Message+'.</p></li></ul>'+
'<p>Apology for the inconvenience.</p></td> </tr>'+
'</table></body></html>');
end;
finally
theResponse.Free;
theHeader := nil;
NetHTTPClient1.Free;
end;
end
else
begin
Result := PChar('<html><head><title>400 Error</title></head>'+
'<body bgcolor="#ffffff" leftmargin="0" topmargin="0" '+
'marginwidth="0" marginheight="0"><table width="75%" '+
'border="0" cellpadding="50" cellspacing="0"><tr>'+
'<td><h3>Bad Request</h3><p>The page you requested could '+
'not be found - due to a 400 error.</p><p>This may have '+
'been caused by the following scenarios:</p><ul><li>'+
'<p>You may have typed the address wrong</p></li><li>'+
'<p> We may have moved the page, created a bad link or '+
'be experiencing temporary problems.</p></li></ul>'+
'<p>Apology for the inconvenience.</p></td> </tr>'+
'</table></body></html>');
end;
end;
exports
GetHTTP, PostHTTP;
begin
end.
and this EXE to call
unit Unit2;
interface
uses
Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls;
type
TForm2 = class(TForm)
WEBResult: TMemo;
HTTPURL: TEdit;
Button1: TButton;
PostData: TMemo;
RequestHeader: TMemo;
Button2: TButton;
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;
var
Form2: TForm2;
function GetHT4TP(theURL,theHeaders, theOptions: PChar): PChar; external 'WEB.dll';
function PostHTTP(theURL,PostData,theHeaders, theOptions: PChar): PChar; external 'WEB.dll';
implementation
{$R *.dfm}
procedure TForm2.Button1Click(Sender: TObject);
begin
WEBResult.Text := String(GetHTTP(PChar(HTTPURL.Text),PChar(RequestHeader.Text), 'No'));
end;
procedure TForm2.Button2Click(Sender: TObject);
begin
WEBResult.Text := String(PostHTTP(PChar(HTTPURL.Text),PChar(PostData.Text),PChar(RequestHeader.Text), 'No'));
end;
end.
Both are compiled by Delphi 10.4 CE on Windows 10 Pro 22H2 x64 without any errors, however, when the EXE is executed it shows this error :
"The program couldn't start correctly (0xc0000142). Click OK to close the program"
I guess I have missed something and can't seem to find it ... fresh eyes would be appreciated enormously !!!
EDIT:
I found out that I just had to remove ShareMem from uses clause and GetHTTP function works as expected, however, PostHTTP shows this error:
"Access violation at address 0000000000D8F4B4 in module 'Library.dll'. Read of address 0000000000000008"
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