Question

TDynByteArray (Array of Byte) - Save to Stream?

Asked by: darrello

I have a SOAP object that is handing back a TDynByteArray (aka Array of Byte) that is a file.

I want to save this array to a TFileStream.  So far I have been able to do it, but it just seems wrong - I am converting the Byte array to a String, and using the TFileStream.WriteBuff(stringVariable,Length(stringVariable) to do it.

Should I not be able to do the following:

    bytesArrayFile:=SOAPObject.ReadFile;
    count:=Length(bytesArrayFile);

    MIMEString:=BytesToString(bytesArrayFile); // Converts the byte array to a string.

    FileStream:=TFileStream.Create('c:\temp\output3.xml',fmCreate);
// THE FOLLOWING LINE OF CODE WORKS - BUT I DON'T THINK I SHOULD BE
// CONVERTING THE BYTE ARRAY TO STRING AND THEN SAVING IT - COULD
// HAVE CONVERSION ISSUES.    
    FileStream.WriteBuffer(PChar(MIMEString)^,Length(MIMEString));


// THE FOLLOWING LINES ARE THINGS I HAVE TRIED - THEY REPLACE THE .WriteBuffer line above


pos:=FileStream.WriteBuffer(bytesArrayFile,DynArrayLength(bytesArrayFile);  // DOESN'T WORK

// THIS LOOP WORKS - BUT IT IS REALLY, REALLY SLOW.
    for i:= 0 to (count - 1) do begin
      FileStream.Write(bytesArrayFile[i],1);
    end;

This Question has been solved and asker verified All Experts Exchange premium technology solutions are available to subscription members.

Subscribe now for full access to Experts Exchange and get

Instant Access to this Solution

  • Plus...
  • 30 Day FREE access, no risk, no obligation
  • Collaborate with the world's top tech experts
  • Unlimited access to our exclusive solution database
  • Never be left without tech help again

Subscribe Now

Asked On
2004-03-02 at 05:06:18ID20903902
Tags

array

,

stream

,

byte

,

save

Topic

Delphi Programming

Participating Experts
2
Points
250
Comments
20

Trusted by hundreds of thousands everyday for fast, accurate and reliable tech support.

  • "The time we save is the biggest benefit of Experts Exchange to Warner Bros. What could take multiple guys 2 hours or more each to find is accessed in around 15 minutes on Experts Exchange." Mike Kapnisakis, Warner Bros.
  • "Our team likes having a resource that is more secure than just using Google and most experts using this service really know their stuff. It's nice to look here first versus using Google." Dayna Sellner, Lockheed Martin
  • "Anytime that I've been stumped with a problem, 9 out of 10 times Experts Exchange has either the accepted solution or an open discussion of the potential solution to the problem." Kenny Red, eBay Inc.

See what Experts Exchange can do for you.

Got a question?

We've got the answer.

Experts Exchange has been collecting answers to technology questions since 1996…3 million and counting! If you have a question, chances are we already have your answer.

Screenshot of Experts Exchange Knowledgebase

Need individual assistance?

Our experts are ready to help.

If you can't find the exact answer you're looking for, ask our exclusive community of 50,000 experts. You’ll get a personalized answer from a trusted professional.

Screenshot of Experts Exchange Knowledgebase

Want to learn from the best?

Read articles from industry experts.

Thousands of free tech tips, tricks, how-to’s and tutorials are available in our peer reviewed articles section. See for yourself how smart our experts are, no login required.

Screenshot of an Article

Working on a long term project?

Store your work and research.

Save solutions to your questions, answers you’ve discovered through searching plus helpful articles in your personal knowledgebase for easy future access.

Screenshot of Experts Exchange Knowledgebase

Access the answers to your technology questions today.

Subscribe Now

30-day free trial. Register in 60 seconds.

What Makes Experts Exchange Unique?

Members of the expert community talk about why the experience at Experts Exchange is different than what you will find anywhere else.

Trusted by the world's most respected brands.

image of each brand's logo

Faithfully serving IT professionals since 1996.

Experts Exchange Logo

Try it out and discover for yourself.

Subscribe Now

30-day free trial. Register in 60 seconds.

Related Solutions

  1. Compress and uncompress TFileStream
    I am looking for the source code of free component that can compressing/uncompressing so as using TFileStream. Thanks for any helping. Ye Chen
  2. TFileStream problem
    Hello... Over a year ago, one of your experts - Andrewjb - answered a question I had regarding how to tack together files programmatically. He suggested using the TFileSTream command and the code example he provided worked great: procedure TForm1.Button1Click(Sender: TObj...
  3. Tfilestream
    hi, the following is an example from a larger project in D3 under WIN98. i extracted it for there is a crazy error: in the Tfilestream.create always getlasterror is 87 !! what is this ?? any ideas ? thanks titz CODE: on the form is only a timer which every 2 secs call...
  4. TFileStream
    I am trying to use TFileSTream but am not getting the result i want. Var fs: TFileStream; s: string; fs := TFileStream.Create('D:\tmp\Data\test.txt',fmOpenRead); fs.Read(s,120); Memo1.Lines.Text := ^s; fs.Free; The routine works fine except that it returns #19 all the time...
  5. TFileStream
    Hello, Can Anyone give me an example how to read from a file with TFileStream? Greetings, Wim
  6. What's wrong with my code? TFileStream / ReadBuffer …
    Could anyone please tell me why this isn't working? function .... var fileStream: TFileStream; total: Integer; toread: Integer; filesize: Longint; I: Integer; begin fileStream := TFileStream.Create(FileName, fmOpenRead); filesize := fileStream.Size; total := ...

Free Tech Articles

  1. WARNING: 5 Reasons why you should NEVER fix a computer for free.
    It is in our nature to love the puzzle. We are obsessed. The lot of us. We love puzzles. We love the challenge. We thrive on finding the answer. We hate disarray. It bothers us deep in our soul. W...
  2. SCCM OSD Basic troubleshooting
    SCCM 2007 OSD is a fantastic way to deploy operating systems, however, like most things SCCM issues can sometimes be difficult to resolve due to the sheer volume of logs to sift through and the dispe...
  3. Migrate Small Business Server 2003 to Exchange 2010 and Windows 2008 R2
    This guide is intended to provide step by step instructions on how to migrate from Small Business Server 2003 to Windows 2008 R2 with Exchange 2010. For this migration to work you will need the fo...
  4. Create a Win7 Gadget
    This article shows you how to create a simple "Gadget" -- a sort of mini-application supported by Windows 7 and Vista. Gadgets can be dropped anywhere on the desktop to provide instant information, ...
  5. Outlook continually prompting for username and password
    There have been a lot of questions recently regarding Outlook prompting for a username and password whilst using Exchange 2007. There are a few reasons why this would happen and I will try to cover t...
  6. Backup Exchange 2010 Information Store using Windows Backup
    There seems to be quite a lot of confusion around the ability to backup Exchange 2010 using the built in Windows Backup feature. This stems from the omission of this feature prior to Exchange 2007 s...

Cloud Class Webinars

  1. Avoiding Bugs in Microsoft Access
    Alison Balter takes and in-depth look at avoiding bugs in Access. In this webinar you will learn about using the immediate window to debug your applications, invoking the debugger, using breakpoints to troubleshoot, stepping through code, setting the next statement to execute, ...
  2. Top 10 Best New Features in Visio 2010
    Scott Helmers gives live demonstrations of the top 10 new features in Visio 2010. This webinar will teach you how to create compelling diagrams by adding shapes to the page with a single click, linking the shapes in a diagram to data in Excel (or SQL Server, or SharePoint), ...
  3. IT Consultant Business Secrets Revealed
    Michael Munger, Experts Exchange tech pro and IT consultant, pulls back the curtain on his very successful businesses and answers question on every IT consultant and business owner should know about. He shares secrets on what he did to solve the 5 most common problems in IT, ...
  4. Disaster Recovery and Business Continuity
    Quest CTO, Mike Billon, gives an overview of the steps involved in building a dunamic disaster recovery plan. Through case studies and an examination of software/hardware tooles for monitoring and testing, you'll gain a better understandin of where you are, where you want ...
  5. Organize Your Visio Diagrams with Containers and Lists
    Scott Helmers uses cross functional flowcharts, wireframe diagrams, data graphic legends and seating charts to teach you: how to ustilize all three new structured diagram components in Visio 2010, the best practices for organizeing shapes in previous version of Visio, how to organize ...
  6. How to Us Objects, Properties, Events and Methods in Microsoft Access
    Alison Dalter gives an in-depbth look at objects, properties, events and methods in Microsoft Access. In this webinar you will learn about using the object browser, referring to objects, working with properties and methods, working with object variables, understanding the ...

Join the Community

Give a Little. Get a Lot.

Join the community of experts here and help other tech pros by answering question in your area of expertise. You can earn FREE access to all Experts Exchange's premium features and resources.

Join the Community

Answers

 

by: kretzschmarPosted on 2004-03-02 at 05:11:11ID: 10494520

hmm just a guess

bytesArrayFile is just a pointer, which points to the beginning
of the memory location of your array

if so, then this change may work
pos:=FileStream.WriteBuffer(bytesArrayFile^,DynArrayLength(bytesArrayFile);

or also
pos:=FileStream.WriteBuffer(@bytesArrayFile,DynArrayLength(bytesArrayFile);

well just guessing,
a test may cause an acces-violation

meikl ;-)

 

by: darrelloPosted on 2004-03-02 at 07:13:46ID: 10495672

Unfortunately that doesn't work.  The WriteBuffer is expecting a point.  When I use the reference/dereference (^,@) Delphi won't even compile.

FileStream.WriteBuffer(fileBytes^,Length(fileBytes)); // doesn't compile "Pointer Type Required"
FileStream.WriteBuffer(@fileBytes,Length(fileBytes)); // doesn't compile "Pointer Type Required"

 

by: kretzschmarPosted on 2004-03-02 at 07:19:20ID: 10495734

well, bad guess,

i don't know what a tdynbytearray is (you say an array of byte -> is it so?).

>object that is handing back a TDynByteArray
TDynByteArray or PDynByteArray ?

meikl ;-)

 

by: darrelloPosted on 2004-03-02 at 07:28:16ID: 10495823

Yes - it is part of Jedi but it is basically a dynamic array declared as Array of Byte

 

by: darrelloPosted on 2004-03-02 at 07:29:04ID: 10495830

From JEDI (Unit is jclBase):

TDynByteArray = array of Byte;

 

by: kretzschmarPosted on 2004-03-02 at 09:38:38ID: 10497069

well, i got it work this way, maybe a bit clumsy

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

  TDynByteArray = array of Byte;

var
  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.Button1Click(Sender: TObject);
var
  b : TDynByteArray;
  i : Integer;
  fs : TFileStream;
begin
  setlength(b,1000);
  for i := 0 to high(b) do
    b[i] := ord('A');
  fs := TFileStream.Create('D:\ByteTest.txt',fmCreate);
  try
    fs.WriteBuffer(pointer(b)^,high(b));
  finally
    fs.free;
  end;
end;

end.

meikl ;-)

 

by: kretzschmarPosted on 2004-03-02 at 09:40:17ID: 10497089

hmm, missed the last entry

replace
    fs.WriteBuffer(pointer(b)^,high(b));
with
    fs.WriteBuffer(pointer(b)^,high(b)+1);

meikl ;-)

 

by: darrelloPosted on 2004-03-02 at 09:54:09ID: 10497224

dang - I am just about to catch a flight - I can't validate this until Friday.  I will give it a whirl though.

 

by: Slick812Posted on 2004-03-02 at 10:17:49ID: 10497449

I have had more success using the First member of a Dynamic array in file stream read and writes , instead of the Pointer Reference to the Dynamic array. . .  maybe

FileStream.Write(bytesArrayFile[0], High(bytesArrayFile));
// although the bytesArrayFile[0] is a single byte, the method does not care, as this is just the starting point to read from

 

by: kretzschmarPosted on 2004-03-02 at 10:26:41ID: 10497518

yep slick,

works also, but you ,ust also increment the high with 1
to get the last entry

    fs.WriteBuffer(b[0],high(b)+1);

meikl ;-)

 

by: Slick812Posted on 2004-03-02 at 10:34:13ID: 10497590

I should have used length(b), although to make it more universal maybe   Length(b)*SizeOf(b[0])
thanks kretzschmar

 

by: darrelloPosted on 2004-03-08 at 18:28:49ID: 10546518

dammit - I meant to split the points - I assume that it is too late?

 

by: Slick812Posted on 2004-03-09 at 13:48:01ID: 10555082

I'm not sure about changing points given after they are rewarded? ? ?  but you can go to the community support  page here at EE and ask the EE guys there

 

by: darrelloPosted on 2004-03-09 at 17:30:09ID: 10556773

I am in favour of unaccepting so I can split it out - they did work together on it.

 

by: darrelloPosted on 2004-03-09 at 17:49:37ID: 10556916

nice to see that you answer questions and admin!  just realized that.

 

by: Slick812Posted on 2004-03-09 at 20:37:18ID: 10557912

I am fine with the outcome of whtever darrello wants to do here. . . .

 

by: darrelloPosted on 2004-03-10 at 04:18:51ID: 10559928

thanks for handling the split.

20120131-EE-VQP-002

3 Ways to Join

30-Day Free Trial

The Experts

98% positive feedback on 31,087 answers since March 2000. angeliii is a Microsoft Most Valuable Professional for his work with MS SQL Server & Develoment.

He has also proven his knowledge of Visual Basic Programming, PHP Scripting and Oracle Databases.

The Experts

97% positive feedback on 10,752 answers since July 2000. lrmoore has more than 18 years experience in the networking industry.

The six-time Mircosoft MVPs specialties include firewalls, virtual private networking, and network management.

Testimonials

"...and excellent source for support... Kind of like having your very own IT dept." Electriciansnet

Testimonials

"I was apprehensive at signing up at first. However... it has already made my life as an IT administrator much easier." JaCrews

Testimonials

"WOW! You guys have great, active, and knowledgeable people on here." moore50

Business Clients

Business Clients

In the Press

"If you’ve got a question... Experts Exchange can supply an answer.”

In the Press

"...an invaluable aid for both IT professionals and those who require tech support."

In the Press

"where IT professionals provide quick answers on just about any topic"

Business Account Plans

Loading Advertisement...