How to get image binary data using XMLHTTPRequest in Delphi - delphi

I need to access binary image data using XMLHttpRequest in Delphi. I am using the following code but its not working, could someone please tell me what's wrong with this code, thanks in advance.
//I am using this function to get Image Binary data into Memory Stream.
procedure SendGETRequest(p_Url: string; p_resStream: TMemoryStream);
begin
FXmlHttpReq.open(METHOD_GET, p_Url, false, FUsername, FPassword);
FXmlHttpReq.setRequestHeader(HTTP_AUTHENTICATION, HTTP_BASIC + EncodeBase64(
FUsername + ':'+FPassword));
FXmlHttpReq.setRequestHeader(HTTP_CACHE_CONTROL, HTTP_NO_CACHE);
//FXmlHttpReq.setRequestHeader('Content-type','application/octet-stream');
FXmlHttpReq.send('');
if not VarIsEmpty(FXmlHttpReq.responseBody) then
begin
p_resStream:= OleVariantToMemoryStream(FXmlHttpReq.responseStream);
end;//if...
end;
function OleVariantToMemoryStream(OV: OleVariant): TMemoryStream;
var
Data: PByteArray;
Size: integer;
begin
Result := TMemoryStream.Create;
try
Size := VarArrayHighBound (OV, 1) - VarArrayLowBound(OV, 1) + 1;
Data := VarArrayLock(OV);
try
Result.Position := 0;
Result.WriteBuffer(Data^, Size);
finally
VarArrayUnlock(OV);
end;
except
Result.Free;
Result := nil;
end;
end;

responseStream is IStream. You need to convert it using TOleStream (AxCtrls):
uses AxCtrls, ComObj, ActiveX;
procedure TForm1.Button1Click(Sender: TObject);
var
oXMLHTTP: OleVariant;
MemoryStream: TMemoryStream;
Stream: IStream;
OleStream: TOleStream;
begin
oXMLHTTP := CreateOleObject('MSXML2.XMLHTTP.3.0');
oXMLHTTP.open('GET', 'https://www.google.com/images/srpr/logo11w.png', False);
oXMLHTTP.send(EmptyParam);
Stream := IUnknown(oXMLHTTP.ResponseStream) as IStream;
OleStream := TOleStream.Create(Stream);
try
OleStream.Position := 0;
MemoryStream := TMemoryStream.Create;
try
MemoryStream.CopyFrom(OleStream, OleStream.Size);
MemoryStream.SaveToFile('logo11w.png');
finally
MemoryStream.Free;
end;
finally
OleStream.Free;
end;
end;

Related

Delphi ZLib Compress / Decompress

I've got a minor issue with decompressing using the ZLib unit in Delphi
unit uZCompression;
interface
uses
uCompression;
type
TZZipCompression = class(TInterfacedObject, ICompression)
public
function DoCompression(aContent: TArray<Byte>): TArray<Byte>;
function DoDecompression(aContent: TArray<Byte>): TArray<Byte>;
function GetWindowsBits: Integer; virtual;
end;
TZGZipCompression = class(TZZipCompression)
function GetWindowsBits: Integer; override;
end;
implementation
uses
System.ZLib, System.Classes, uMxKxUtils;
{ TZCompression }
function TZZipCompression.DoCompression(aContent: TArray<Byte>): TArray<Byte>;
var
LContentStream, LOutputStream: TMemoryStream;
LCompressedStream: TZCompressionStream;
begin
LContentStream := ByteArrayToStream(aContent);
LOutputStream := TMemoryStream.Create;
LCompressedStream := TZCompressionStream.Create(LOutputStream, zcDefault, GetWindowsBits);
LCompressedStream.CopyFrom(LContentStream, LContentStream.Size);
LCompressedStream.Free;
Result := StreamToByteArray(LOutputStream);
LOutputStream.Free;
LContentStream.Free;
end;
function TZZipCompression.DoDecompression(aContent: TArray<Byte>): TArray<Byte>;
var
LContentStream, LOutputStream: TMemoryStream;
LDecompressedStream: TZDecompressionStream;
begin
LContentStream := ByteArrayToStream(aContent);
LOutputStream := TMemoryStream.Create;
LDecompressedStream := TZDecompressionStream.Create(LContentStream);
LOutputStream.CopyFrom(LDecompressedStream, LDecompressedStream.Size);
LDecompressedStream.Free;
Result := StreamToByteArray(LOutputStream);
LOutputStream.Free;
LContentStream.Free;
end;
function TZZipCompression.GetWindowsBits: Integer;
begin
Result := 15;
end;
{ TZGZipCompression }
function TZGZipCompression.GetWindowsBits: Integer;
begin
Result := inherited;
Result := Result + 16;
end;
end.
This is my unit which is driven by an interface (which you don't need to know about), and data is passed in and out through a TArray variables.
I've coded it to be able to do 2 types of compression, standard zip and gzip which is determined by the windowsbits passed in to the functions.
Here are a couple of other functions being used to convert the TArray to TMemoryStream
function ByteArrayToStream(aContent: TArray<Byte>): TMemoryStream;
begin
Result := TMemoryStream.Create;
Result.Write(aContent, length(aContent)*SizeOf(aContent[0]));
Result.Position := 0;
end;
function StreamToByteArray(aStream: TMemoryStream): TArray<Byte>;
var
LStreamPos: Int64;
begin
if Assigned(aStream) then
begin
LStreamPos := aStream.Position;
aStream.Position := 0;
SetLength(Result, aStream.Size);
aStream.Read(Result, aStream.Size);
aStream.Position := LStreamPos;
end
else
SetLength(Result, 0);
end;
Now I can compress and decompress to .zip using the TZZipCompression class perfectly fine (it doesn't open up as a zip file, but it does decompress back to the original file which I can open and edit).
I can also compress to .gz using the TZGZipCompression class fine as well (interestingly I can open this gzip file perfectly well).
My issue however is that it won't decompress back from the .gz file and throws and error as soon as it hits
LOutputStream.CopyFrom(LDecompressedStream, LDecompressedStream.Size)
Funnily enough the Help file example has it as below
LOutputStream.CopyFrom(LDecompressedStream, 0)
But this doesn't work either.
Can anyone spot the issue?
Your conversion functions between TArray<Byte> and TMemoryStream are wrong, as you are not accessing the array content correctly. TArray is a dynamic array. When calling TMemoryStream.Write() and TMemoryStream.Read(), you are passing the memory address of the TArray itself, not the memory address of the data that the TArray points at. You need to reference the TArray to get the correct memory address, eg:
function ByteArrayToStream(const aContent: TArray<Byte>): TMemoryStream;
begin
Result := TMemoryStream.Create;
try
if Length(aContent) > 0 then
Result.WriteBuffer(aContent[0], Length(aContent));
Result.Position := 0;
except
Result.Free;
raise;
end;
end;
function StreamToByteArray(aStream: TMemoryStream): TArray<Byte>;
begin
if Assigned(aStream) then
begin
SetLength(Result, aStream.Size);
if Length(Result) > 0 then
Move(aStream.Memory^, Result[0], aStream.Size);
end
else
SetLength(Result, 0);
end;
Alternatively:
function ByteArrayToStream(const aContent: TArray<Byte>): TMemoryStream;
begin
Result := TMemoryStream.Create;
try
Result.WriteBuffer(PByte(aContent)^, Length(aContent));
Result.Position := 0;
except
Result.Free;
raise;
end;
end;
function StreamToByteArray(aStream: TMemoryStream): TArray<Byte>;
begin
if Assigned(aStream) then
begin
SetLength(Result, aStream.Size);
Move(aStream.Memory^, PByte(Result)^, aStream.Size);
end
else
SetLength(Result, 0);
end;
That being said, you don't need to waste memory making copies of the array data using TMemoryStream. You can use TBytesStream instead (since dynamic arrays are reference counted), eg:
function TZZipCompression.DoCompression(aContent: TArray<Byte>): TArray<Byte>;
var
LContentStream, LOutputStream: TBytesStream;
LCompressedStream: TZCompressionStream;
begin
LContentStream := TBytesStream.Create(aContent);
try
LOutputStream := TBytesStream.Create(nil);
try
LCompressedStream := TZCompressionStream.Create(LOutputStream, zcDefault, GetWindowsBits);
try
LCompressedStream.CopyFrom(LContentStream, 0);
finally
LCompressedStream.Free;
end;
Result := Copy(LOutputStream.Bytes, 0, LOutputStream.Size);
finally
LOutputStream.Free;
end;
finally
LContentStream.Free;
end;
end;
function TZZipCompression.DoDecompression(aContent: TArray<Byte>): TArray<Byte>;
var
LContentStream, LOutputStream: TBytesStream;
LDecompressedStream: TZDecompressionStream;
begin
LContentStream := TBytesStream.Create(aContent);
try
LOutputStream := TBytesStream.Create(nil);
try
LDecompressedStream := TZDecompressionStream.Create(LContentStream, GetWindowsBits);
try
LOutputStream.CopyFrom(LDecompressedStream, 0);
finally
LDecompressedStream.Free;
end;
Result := Copy(LOutputStream.Bytes, 0, LOutputStream.Size);
finally
LOutputStream.Free;
end;
finally
LContentStream.Free;
end;
end;

Using TIdCompressorLib to Decompress gzip file

I am using Delphi 2007 with Indy 10. I have a gzip file. I have verified it can be decompressed with this Online Decompression Tool.
I am trying to use the TIdCompressorZlib component to decompress using Delphi. Here is my code:
procedure TForm2.Button9Click(Sender: TObject);
var
lCompressor : TIdCompressorZLib;
FileStream : TFileStream;
memorystream: TMemoryStream;
begin
lCompressor := TIdCompressorZLib.create(self);
FileStream := TFileStream.Create('c:\temp\test.gz', fmOpenRead);
filestream.position := 0;
memorystream:= TMemoryStream.create;
memorystream.position := 0;
lcompressor.DecompressGZipStream(FileStream,MemoryStream);
filestream.free;
showmessage('done');
end;
I cannot get it to work. If I pass fmOpenReadWrite in the constructor I get a zlib error (-5) when DecompressGZipStream is called.
If I pass fmOpenRead in the constructor I get a OS System Error Code 5 Access Denied when DecompressGZipStream is called.
Update David Hefferan suggested it is a file reading issue. So I am zeroing in on that. I am able to copy the file using this procedure:
Procedure FileCopy( Const sourcefilename, targetfilename: String );
Var
S, T: TFileStream;
Begin
S := TFileStream.Create( sourcefilename, fmOpenRead );
try
T := TFileStream.Create( targetfilename,
fmOpenWrite or fmCreate );
try
T.CopyFrom(S, S.Size ) ;
finally
T.Free;
end;
finally
S.Free;
end;
showmessage('done');
End;
UPD Per David Heffernan, I have verified I can Read the data. I successfully ran the file through the following function. It returns the proper number of characters (bytes):
function GetTextFromFile(AFile: string; var Returnstring: string): Boolean;
var
FileStream: TFileStream;
begin
Result := False;
if not FileExists(AFile) then Exit;
FileStream := TFileStream.Create(AFile, fmOpenRead);
try
if FileStream.Size <> 0 then
begin
SetLength(Returnstring, FileStream.Size);
FileStream.Read(Returnstring[1], FileStream.Size);
Result := True;
end;
finally
FileStream.Free;
end;
end;
You can try to use Delphi zlib unit to decompress gzip.
Sample code:
procedure TForm2.Button9Click(Sender: TObject);
var
DecompressionStream : TDecompressionStream;
FileStream : TFileStream;
dest: TFileStream;
byteCount: Integer;
buffer: array [0..65535] of Byte;
begin
FileStream := TFileStream.Create('c:\temp\test.gz', fmOpenRead);
try
//no need to set FileStream position to 0, it's there already
DecompressionStream:=TDecompressionStream.Create(FileStream, 15+16);
//16 is flag that gzip stream used, not zlib.
//15 is maximum memory usage, to speed-up decompression.
try
dest:=TFileStream.Create('c:\temp\test.txt', fmCreate);
try
dest.CopyFrom(DecompressionStream,0);
finally
dest.free;
end;
finally
DecompressionStream.free;
end;
finally
filestream.free;
end;
showmessage('done');
end;
UPD: this code doesn't work for D2007 or earlier versions, no overloaded constructor with WindowBits argument...

how to convert idhttp downloaded image from extention to another?

i have this Thread that get image url from the web then save it to memory stream then save from memory stream To file
i needed to convert any image that downloaded to a gif image so i do something like this
unit downloadimgThread;
interface
uses Windows, SysUtils, Classes, dialogs, IdSSLOpenSSL, IdHttp, IdUri, System.AnsiStrings, Graphics, Jpeg, Vcl.Imaging.GIFImg, PNGImage;
type
TDownloadUpdateVisualEvent = procedure(Sender: TObject; Anameofimg: String;
var Aimagelocate: String) of object;
type
TURLDownload = class(TThread)
private
FOnUpdateVisual: TDownloadUpdateVisualEvent;
FURL: String;
Fnameofimg: string;
FPathImage: string;
FFileNameImage: string;
ImageName: string;
PathURL: string;
procedure DoUpdateVisual;
protected
procedure Execute; override;
public
constructor Create(Thrdid: Pointer; const AUrl: String;
Const AOutPathImages: string; AOnUpdateVisual: TDownloadUpdateVisualEvent;
Anameofimg: String); reintroduce;
property URL: string read FURL write FURL;
property PathImage: string read FPathImage;
property FileNameImage: string read FFileNameImage;
end;
var
URLDOWNLOAD: TURLDownload;
implementation
{ TURLDownload }
function JpgToGif(ms: TMemoryStream): Boolean;
var
gif: TGIFImage;
jpg: TJPEGImage;
begin
Result := False;
gif := TGIFImage.Create;
try
jpg := TJPEGImage.Create;
try
//jpg
ms.Position := 0;
jpg.LoadFromStream(ms);
jpg.DIBNeeded;
gif.Assign(jpg);
//save...
ms.Clear;
gif.SaveToStream(ms);
Result := True;
finally
jpg.Free;
jpg := nil;
end;
finally
gif.Free;
gif := nil;
end;
end;
constructor TURLDownload.Create(Thrdid: Pointer; const AUrl, AOutPathImages: string; AOnUpdateVisual: TDownloadUpdateVisualEvent; Anameofimg: String);
var
URI: TIdURI;
begin
inherited Create(false);
FreeOnTerminate := True;
FURL := AUrl;
FOnUpdateVisual := AOnUpdateVisual;
Fnameofimg := Anameofimg;
FPathImage := AOutPathImages;
URI := TIdURI.Create(AUrl);
try
ImageName := URI.Document;
PathURL := URI.path;
finally
URI.Free;
end;
end;
procedure TURLDownload.DoUpdateVisual;
begin
if Assigned(FOnUpdateVisual) then
FOnUpdateVisual(self, Fnameofimg, FFileNameImage);
end;
procedure TURLDownload.Execute;
var
aMs: TMemoryStream;
aIdHttp: TIdHttp;
IdSSL: TIdSSLIOHandlerSocketOpenSSL;
path: string;
dir: string;
SPEXT : String;
itsimage: string;
responsechk: Integer;
begin
dir := AnsiReplaceText(PathURL, '/', '');
if (ImageName = '') then
begin
exit;
end;
SPEXT := ExtractFileExt(ImageName);
ImageName := Copy(ImageName, 1, Length(ImageName) - Length(SPEXT));
path := PathImage + '\' + ImageName + '.gif';
if fileexists(path) then
begin
FFileNameImage := path;
if Assigned(FOnUpdateVisual) then
begin
Synchronize(DoUpdateVisual);
end;
exit;
end
else
if not fileexists(path) then
begin
aMs := TMemoryStream.Create;
aIdHttp := TIdHttp.Create(nil);
IdSSL := TIdSSLIOHandlerSocketOpenSSL.Create(nil);
try
IdSSL.SSLOptions.Method := sslvTLSv1;
IdSSL.SSLOptions.Mode := sslmUnassigned;
aIdHttp.HTTPOptions := [hoForceEncodeParams] + [hoNoProtocolErrorException];
aIdHttp.IOHandler := IdSSL;
aIdHttp.AllowCookies := True;
aIdHttp.Request.UserAgent := 'Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0) Gecko/20100101 Firefox/12.0';
aIdHttp.HandleRedirects := True;
aIdHttp.RedirectMaximum := 3;
try
aIdHttp.Head(trim(FURL));
except
end;
itsimage := aIdHttp.Response.ContentType;
responsechk := aIdHttp.ResponseCode;
if responsechk <> 200 then
begin
FFileNameImage := 'error';
if Assigned(FOnUpdateVisual) then
begin
Synchronize(DoUpdateVisual);
end;
exit;
end;
if (itsimage = 'image/gif') then
begin
try
aIdHttp.Get(trim(FURL), aMs);
except
end;
aMs.SaveToFile(path);
end else if (itsimage = 'image/jpeg') then
begin
try
aIdHttp.Get(trim(FURL), aMs);
except
end;
if JpgToGif(aMs) then
begin
aMs.SaveToFile(path);
end;
end;
try
if aIdHttp.Connected then
aIdHttp.Disconnect;
except
end;
finally
aMs.Free;
IdSSL.Free;
aIdHttp.Free;
end;
end;
FFileNameImage := path;
if Assigned(FOnUpdateVisual) then
begin
Synchronize(DoUpdateVisual);
end;
end;
end.
in this unit i try to check if image type is jpg then convert it to gif and save it specifically at this line of code
if (itsimage = 'image/jpeg') then
begin
try
aIdHttp.Get(trim(FURL), aMs);
except
end;
if JpgToGif(aMs) then
begin
aMs.SaveToFile(path);
end;
// function to convert
function JpgToGif(ms: TMemoryStream): Boolean;
var
gif: TGIFImage;
jpg: TJPEGImage;
begin
Result := False;
gif := TGIFImage.Create;
try
jpg := TJPEGImage.Create;
try
//jpg
ms.Position := 0;
jpg.LoadFromStream(ms);
jpg.DIBNeeded;
gif.Assign(jpg);
//save...
ms.Clear;
gif.SaveToStream(ms);
Result := True;
finally
jpg.Free;
jpg := nil;
end;
finally
gif.Free;
gif := nil;
end;
end;
when i try to convert the image and save it the image saved is corrupted what could be the issue ?
There is a very simple solution for this. And that is to use FMX Bitmap instead of default VCL Bitmap as it allows automatic format recognition on load and automatic format choosing on save based on file extension of the file name you provide to SaveToFile method.
Here is a simple code that loads selected image chosen in OpenDialog into Memory stream first and then into Bitmap and then it saves the image into GIF format.
procedure TForm1.Button1Click(Sender: TObject);
var Bitmap: FMX.Graphics.TBitmap;
MS: TMemoryStream;
begin
if OpenDialog1.Execute then
begin
MS := TMemoryStream.Create;
MS.LoadFromFile(OpenDialog1.FileName);
Bitmap := FMX.Graphics.TBitmap.Create;
Bitmap.LoadFromStream(MS);
Bitmap.SaveToFile('D:\Proba.gif');
end;
end;
As you can see you only need just a few lines and you get ability to convert images between all supported formats.
You can see which ones are supported here:
http://docwiki.embarcadero.com/Libraries/XE8/en/FMX.Graphics.TBitmapCodecManager#Supported_Image_Formats
Just make sure you are indeed using FMX.Graphics.TBitmap by specifying the full namespace for the file in which it resided.
NOTE: Working on VCL application does not mean you can't use some of the functionality that is present in Fire Monkey.

Udp image streaming, delphi indy10

i'm using delphi xe4 with indy10 component and i want to send an image from an Tidudpclient to Tidudpserver. I already done this operation with tcp component,but the same code didn't work with udp. how i can do this?
Thanks in advance!
Timage(client)--->streamUDP-->Timage(server)
CLIENT SIDE----------------------------------------------- SEND IMAGE
var
pic: tbitmap;
Strm : TMemoryStream;
img2:Timage;
buffer:TIdBytes;
begin
try
img2:=Timage.Create(nil);
pic:=Tbitmap.Create;
Takekpic(pic);
BMPtoJPG(pic,img2);
Strm := TMemoryStream.Create;
img2.Picture.bitmap.SaveToStream(strm);
Strm.Position:=0;
ReadTIdBytesFromStream(Strm,buffer,SizeOf(Strm),0);
IdTrivialFTPServer1.SendBuffer('192.168.17.128',1234,buffer);
finally
strm.Free;
end;
end;
SERVER SIDE---------------------------------------------------- READ IMAGE
procedure TForm6.IdTrivialFTP1UDPRead(AThread: TIdUDPListenerThread;
const AData: TIdBytes; ABinding: TIdSocketHandle);
var
Strm : TMemoryStream;
Jpg: TJpegImage;
begin
Strm := TMemoryStream.Create;
try
WriteTIdBytesToStream(Strm,AData,SizeOf(AData),0);
strm.Position:=0;
Jpg := TJpegImage.Create;
jpg.LoadFromStream(Strm); <---- error while reading (JPEG Error #53)
img1.Picture.assign(jpg);
finally
strm.Free;
Jpg.Free;
end;
end;
what can be wrong in this code?
TIdUDPClient and TIdUDPServer do not support sending/receiving TStream data. You can save your image data into a TStream, but you will have to send/receive it using TIdBytes chunks.
Alternatively, use TIdTrivialFTP and TIdTrivialFTPServer instead, which implement TFTP, a UDP-based file transfer protocol. They operate using TStream objects
Update: for example:
Client:
var
bmp: TBitmap;
jpg: TJPEGImage;
Strm : TMemoryStream;
begin
Strm := TMemoryStream.Create;
try
jpg := TJPEGImage.Create;
try
bmp := TBitmap.Create;
try
Takekpic(bmp);
jpg.Assign(bmp);
finally
bmp.Free;
end;
jpg.SaveToStream(Strm);
finally
jpg.Free;
end;
Strm.Position := 0;
{
These can be assigned ahead of time...
IdTrivialFTP1.Host := '192.168.17.128';
IdTrivialFTP1.Port := 1234;
}
IdTrivialFTP1.Put(Strm, 'image.jpg');
finally
Strm.Free;
end;
end;
Server:
procedure TForm6.IdTrivialFTPServer1WriteFile(Sender: TObject; var FileName: String; const PeerInfo: TPeerInfo; var GrantAccess: Boolean; var AStream: TStream; var FreeStreamOnComplete: Boolean) of object;
begin
if FileName = 'image.jpg' then
begin
GrantAccess := True;
AStream := TMemoryStream.Create;
FreeStreamOnComplete := True;
end else
GrantAccess := False;
end;
{
If you set TIdTrivialFTPServer.ThreadedEvent to False, this event handler
runs in the context of the main thread, so the UI can be accessed safely.
If you set IdTrivialFTPServer.ThreadedEvent to True, this event handler
runs in the context of a worker thread, so you will have to manually
synchronize with the main thread when updating the UI...
}
procedure TForm6.IdTrivialFTPServer1TransferComplete(Sender: TObject; const Success: Boolean; const PeerInfo: TPeerInfo; var AStream: TStream; const WriteOperation: Boolean);
var
jpg: TJPEGImage;
begin
if WriteOperation and Success then
begin
jpg := TJPEGImage.Create;
try
AStream.Position := 0;
jpg.LoadFromStream(AStream);
img1.Picture.Assign(jpg);
finally
jpg.Free;
end;
end;
end;

Posting Data with Indy and Receiving it to TWebBrowser

I am trying to post data to bing with this code
function PostExample: string;
var
lHTTP: TIdHTTP;
lParamList: TStringList;
begin
lParamList := TStringList.Create;
lParamList.Add('q=test');
lHTTP := TIdHTTP.Create(nil);
try
Result := lHTTP.Post('http://www.bing.com/', lParamList);
finally
FreeAndNil(lHTTP);
FreeAndNil(lParamList);
end;
end;
And then, how can I get the result to the TWebBrowser and display it?
Try LoadDocFromString:
procedure LoadBlankDoc(ABrowser: TWebBrowser);
begin
ABrowser.Navigate('about:blank');
while ABrowser.ReadyState <> READYSTATE_COMPLETE do
begin
Application.ProcessMessages;
Sleep(0);
end;
end;
procedure CheckDocReady(ABrowser: TWebBrowser);
begin
if not Assigned(ABrowser.Document) then
LoadBlankDoc(ABrowser);
end;
procedure LoadDocFromString(ABrowser: TWebBrowser; const HTMLString: wideString);
var
v: OleVariant;
HTMLDocument: IHTMLDocument2;
begin
CheckDocReady(ABrowser);
HTMLDocument := ABrowser.Document as IHTMLDocument2;
v := VarArrayCreate([0, 0], varVariant);
v[0] := HTMLString;
HTMLDocument.Write(PSafeArray(TVarData(v).VArray));
HTMLDocument.Close;
end;
Or you can use the memory streams for loading
uses
OleCtrls, SHDocVw, IdHTTP, ActiveX;
function PostRequest(const AURL: string; const AParams: TStringList;
const AWebBrowser: TWebBrowser): Boolean;
var
IdHTTP: TIdHTTP;
Response: TMemoryStream;
begin
Result := True;
try
AWebBrowser.Navigate('about:blank');
while AWebBrowser.ReadyState < READYSTATE_COMPLETE do
Application.ProcessMessages;
Response := TMemoryStream.Create;
try
IdHTTP := TIdHTTP.Create(nil);
try
IdHTTP.Post(AURL, AParams, Response);
if Response.Size > 0 then
begin
Response.Position := 0;
(AWebBrowser.Document as IPersistStreamInit).Load(
TStreamAdapter.Create(Response, soReference));
end;
finally
IdHTTP.Free;
end;
finally
Response.Free;
end;
except
Result := False;
end;
end;
procedure TForm1.Button1Click(Sender: TObject);
var
Params: TStringList;
begin
Params := TStringList.Create;
try
Params.Add('q=test');
if not PostRequest('http://www.bing.com/', Params, WebBrowser1) then
ShowMessage('An unexpected error occured!');
finally
Params.Free;
end;
end;

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