Is there a way to get the RTF data from a richedit without using savetostream as in
strStream := TStringStream.Create('') ;
try
RichEdit.Lines.SaveToStream(strStream);
Text := strStream.DataString;
strStream.CleanupInstance;
finally
strStream.Free
Tim the only way to get the RTF data from an RichEdit control is using a Stream because the windows message (EM_STREAMOUT) wich retrieve the RTF Data require a EditStreamCallback structure, this is the way used by windows to transfer rtf data into or out of a richedit control.
So you can use your own sample code, or implement the call to the windows message EM_STREAMOUT.
function RichTextToStr(red : TRichEdit) : string;
var ss : TStringStream;
begin
ss := TStringStream.Create('');
try
red.Lines.SaveToStream(ss);
Result := ss.DataString;
finally
ss.Free;
end;
end;
procedure CopyRTF(redFrom,redTo : TRichEdit);
var s : TMemoryStream;
begin
s := TMemoryStream.Create;
try
redFrom.Lines.SaveToStream(s);
s.Position := 0;
redTo.Lines.LoadFromStream(s);
finally
s.Free;
end;
end;
I can attest deviation from the pattern results in frustration....
Related
DevExpress doesn't provide docs about "How to programmatically add and get rich text using a TdxRichEditControl".
Or Any suggestion to Embedded Full text Editor in my program? I am on Delphi Seattle.
My Situation:
I am creating a program on which the user need rich text editing (like Bold, Italic, Underlining, Font Size, Font family, Paragraph Aligning). So I've putted a DBRichEdit that load a model of text on which the user will make changes.
So I need to take this model text to the TdxRichEditControl to apply the changes and back it again to the DBRichEdit to save it in the database.
If you want to just insert portions of text into the control, this is some code I used to use for copying from one DevExpress RichEdit to another.. You might be able to adapt it to copy from another source (warning - it's a few years old):
procedure AppendToRichEdit(const Source, Dest: TcxRichEdit) ;
var
RTFStream: TEditStream;
Stream : TMemoryStream;
function EditStreamReader(dwCookie: DWORD; pBuff: Pointer; cb: LongInt; pcb: PLongInt): DWORD; stdcall;
begin
Result := $0000;
try
pcb^ := TStream(dwCookie).Read(pBuff^, cb);
except
Result := $FFFF;
end;
end;
begin
Stream := TMemoryStream.Create;
try
Source.Lines.SaveToStream(Stream) ;
Stream.Position := 0;
RTFStream.dwCookie := DWORD(Stream) ;
RTFStream.dwError := $0000;
RTFStream.pfnCallback := #EditStreamReader;
Dest.InnerControl.Perform(EM_STREAMIN, SFF_SELECTION or SF_RTF or SFF_PLAINRTF, LPARAM(#RTFStream)) ;
if RTFStream.dwError <> $0000 then
raise Exception.Create('Error appending RTF data.') ;
finally
Stream.Free;
end;
end;
I'm modifying a program that is written in Delphi 6.0
I have a table in Oracle with a BLOB column named FILE_CONTENT.
I have already managed to upload an XML File that is about 100 KB. I have verified that the file content was correctly uploaded using SQL Developer.
The problem I have is when I try to download back the file content from DB to a file. This is an example code I'm using to donwload it:
procedure TfrmDownload.Save();
var
fileStream: TFileStream;
bField: TBlobField;
begin
dmDigital.qrGetData.Open;
dmDigital.RequestLive := True;
bField := TBlobField(dmDigital.qrGetData.FieldByName('FILE_CONTENT'));
fileStream := TFileStream.Create('FILE.XML', fmCreate);
bField.SaveToStream(fileStream);
FlushFileBuffers(fileStream.Handle);
fileStream.Free;
dmDigital.qrGetData.Close;
end;
The previous code already downloads the file content to FILE.XML. I'm using RequestLive:=True to be able to download a large BLOB (otherwise the file content is truncated to 32K max)
The resulting file is the same size as the original file. However, when I compare the downloaded file with the original one there are some differences (for example the last character is missing and other characters are also changed), therefore it seems to be a problem while downloading the content.
Do you know what cuould be wrong?
The problem seems to be related to Delphi code because I already tried with C# and the file content is downloaded correctly.
Don't use TBlobField.SaveToStream() directly, use TDataSet.CreateBlobStream() instead (which is what TBlobField.SaveToStream() uses internally anyway):
procedure TfrmDownload.Save;
var
fileStream: TFileStream;
bField: TField;
bStream: TStream;
begin
dmDigital.qrGetData.Open;
try
dmDigital.RequestLive := True;
bField := dmDigital.qrGetData.FieldByName('FILE_CONTENT');
bStream := bField.DataSet.CreateBlobStream(bField, bmRead);
try
fileStream := TFileStream.Create('FILE.XML', fmCreate);
try
fileStream.CopyFrom(bStream, 0);
FlushFileBuffers(fileStream.Handle);
finally
fileStream.Free;
end;
finally
bStream.Free;
end;
finally
dmDigital.qrGetData.Close;
end;
end;
TDataSet.CreateBlobStream() allows the DataSet to decide the best way to access the BLOB data. If the returned TStream is not delivering the data correctly, then either the TStream class implementation that CreateBlobStream() uses is broken, or the underlying DB driver is buggy. Try taking CopyFrom() out of the equation so you can verify the data as it is being retrieved:
procedure TfrmDownload.Save;
const
MaxBufSize = $F000;
var
Buffer: array of Byte;
N: Integer;
fileStream: TFileStream;
bField: TField;
bStream: TStream;
begin
dmDigital.qrGetData.Open;
try
dmDigital.RequestLive := True;
bField := dmDigital.qrGetData.FieldByName('FILE_CONTENT');
bStream := bField.DataSet.CreateBlobStream(bField, bmRead);
try
fileStream := TFileStream.Create('FILE.XML', fmCreate);
try
//fileStream.CopyFrom(bStream, 0);
SetLength(Buffer, MaxBufSize);
repeat
N := bStream.Read(PByte(Buffer)^, MaxBufSize);
if N < 1 then Break;
// verify data here...
fileStream.WriteBuffer(PByte(Buffer)^, N);
until False;
FlushFileBuffers(fileStream.Handle);
finally
fileStream.Free;
end;
finally
bStream.Free;
end;
finally
dmDigital.qrGetData.Close;
end;
end;
I am downloading an EXE file from internet using Indy (idHTTP), and I can use memorystream or filestream to save it to disk, but I really do not know if there is any difference between them (maybe in the result structure of the file?). I could't find yet an answer for this.
Where, here are 2 simple functions to simulate what I am doing:
Function DownloadMS(FUrl, Dest: String): Boolean;
var
Http: TIdHTTP;
Strm: TMemoryStream;
Begin
Result := False;
Http := TIdHTTP.Create;
Strm := TMemoryStream.Create;
With Http, Strm Do
Try
Try
Get(FUrl, Strm);
If (Size > 0) Then
Begin
Position := 0;
SaveToFile(Dest);
Result := True;
end;
Except
end;
Finally
Strm.Free;
Http.Free;
end;
end;
Function DownloadFS(FUrl, Dest: String): Boolean;
var
Http: TIdHTTP;
Strm: TFileStream;
Begin
Result := False;
Http := TIdHTTP.Create;
Strm := TFileStream.Create(Dest, fmCreate);
With Http, Strm Do
Try
Try
Get(FUrl, Strm);
Result := (Size > 0);
Except
end;
Finally
Strm.Free;
Http.Free;
end;
end;
What you experts think about using one or other type (memorystream or filestream)? Is there any difference in the structure of the EXE file when using one or other type? What type is recommended?
Thank you! Have a nice weekend!
There is no difference between TMemoryStream or TFileStream from the stream point of view.
They are both streams and hold a stream of bytes and are both derived from TStream.
You can implement your function generalized like this
function DownloadToStream( const AUrl : String; ADest : TStream ): Boolean;
var
LHttp: TIdHTTP;
begin
LHttp := TIdHTTP.Create;
try
LHttp.Get( AUrl, ADest );
Result := ADest.Size > 0;
finally
LHttp.Free;
end;
end;
and call it with a TFileStream
var
LStream : TStream;
begin
LStream := TFileStream.Create( 'MyFile.exe', fmCreate );
if DownloadToStream( '', LStream ) then
...
end;
or TMemoryStream or whatever stream instance you like
In many cases there will be no point in putting an intermediate memory stream in between the download and the file. All that will do is consume memory because you have to put the entire file in memory before you can put it to disk. Using a file stream directly avoids that issue.
The main situation where the file stream option has problems is if you want to be sure that you've downloaded the entire file successfully before saving to disk. For example, if you are overwriting a previous version of a file, you may want to download it, check a hash signature, and only then overwrite the original file. In that scenario you need to put the file to some temporary location before over-writing. You could use a memory stream, or you could use a file stream using a temporary file name.
How can I get source code from WebBrowser component?
I want to get source code of active page on WebBrowser component and write it to a Memo component.
Thanks.
You can use the IPersistStreamInit Interface and the save method to store the content of the Webbrowser in a Stream.
Uses
ActiveX;
function GetWebBrowserHTML(const WebBrowser: TWebBrowser): String;
var
LStream: TStringStream;
Stream : IStream;
LPersistStreamInit : IPersistStreamInit;
begin
if not Assigned(WebBrowser.Document) then exit;
LStream := TStringStream.Create('');
try
LPersistStreamInit := WebBrowser.Document as IPersistStreamInit;
Stream := TStreamAdapter.Create(LStream,soReference);
LPersistStreamInit.Save(Stream,true);
result := LStream.DataString;
finally
LStream.Free();
end;
end;
That works well too:
uses MSHTML;
function GetHTML(w: TWebBrowser): String;
Var
e: IHTMLElement;
begin
Result := '';
if Assigned(w.Document) then
begin
e := (w.Document as IHTMLDocument2).body;
while e.parentElement <> nil do
begin
e := e.parentElement;
end;
Result := e.outerHTML;
end;
end;
This has been asked and answered many times in the Embarcadero forums, with plenty of code examples posted. Search the archives.
The gist of it is that you Navigate() to the desired URL and wait for the OnDocumentComplete event to fire, then QueryInterface() the Document property for the IPersistStreamInit interface and call its save() method. Create a TStream object instance, such as a TMemoryStream, wrap it in a TStreamAdapter object, and then pass the adapter to save(). You can then load the TStream into the TMemo as needed.
Why not Quick and Dirty:
OnNavigateComplete2()
Form1.RichEdit1.Text:=(WebBrowser1.OleObject.Document.documentElement.outerhtml);
How can I get content of an exe file and convert it into Base64 encoding ?
Edit
I use D2010 and I want to know how is it possible exactly ?
open an exe file
convert its content into base64
In Delphi 2009/2010/XE there is unit EncdDecd.pas (Soap.EncdDecd.pas for Delphi XE2) containing the functions EncodeBase64 and DecodeBase64. You can load the exe file into a memorystream and then call EncodeBase64.
function EncodeFile(const FileName: string): AnsiString;
var
stream: TMemoryStream;
begin
stream := TMemoryStream.Create;
try
stream.LoadFromFile(Filename);
result := EncodeBase64(stream.Memory, stream.Size);
finally
stream.Free;
end;
end;
In ancient Delphi versions, you can use synapse (link here)
Just put synacode.pas in your uses e call EncodeBase64/EncodeBase64.
Cheers
As also mentioned in the comments, since Delphi XE8 you can use the System.NetEncoding.TNetEncoding.Base64 class property.
It also returns a string instead of an AnsiString:
function TryEncodeFile(const AFileName: string; out ABase64string: string): Boolean;
var
MemStream: TMemoryStream;
begin
MemStream := TMemoryStream.Create;
try
MemStream.LoadFromFile(AFileName);
ABase64string :=
TNetEncoding.Base64.EncodeBytesToString(MemStream.Memory, MemStream.Size);
Result := True;
finally
MemStream.Free;
end;
end;