Solved

Super easy question...

Posted on 1998-12-05
8
137 Views
Last Modified: 2010-04-06
I'm new to Delphi and would like to know how to read a text file into a string.  It has to be fast because the file it's reading could be over 5 MB's.

Thanks.
0
Comment
Question by:dokken
  • 4
  • 3
8 Comments
 
LVL 17

Expert Comment

by:inthe
ID: 1349456
hi,
use loadfromfile with begin and end update ie:

application.processmessages;
memo1.lines.beginupdate;
memo1.lines.loadfromfile(c:\autoexec.bat);
memo1.lines.enupdate;

a good way to load a large file is to show a splash screen while its loading
Barry

0
 
LVL 17

Expert Comment

by:inthe
ID: 1349457
quick syntax check...


memo1.lines.beginupdate;
application.processmessages;
memo1.lines.loadfromfile('c:\autoexec.bat');
memo1.lines.endupdate;

Barry

0
 

Author Comment

by:dokken
ID: 1349458
I already know how to load it into a memo and rich text box... but I only want it load into a string.  The file is going to get very big, so I don't want any limitations or anything slowing it down.
0
 

Author Comment

by:dokken
ID: 1349459
Or, what might be better, if the rich text box's savetofile can save the text as text and not RTF and handle over 200,000 lines.
0
Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

 
LVL 17

Expert Comment

by:inthe
ID: 1349460
hi
sorry ok what about

var
mystring:tstringlist;
begin
mystring:=tstringlist.create;
mystring.loadfromfile('c:\autoexec.bat');
{do whatever with your string}
end

this will read your file into 'mystring' im memory and should be quite fast enough, the size wont be a prob stringlists can handle up to 2gig.
is this more on the right lines for your question?
0
 

Author Comment

by:dokken
ID: 1349461
Thats works great, put it as the answer so I can give you the points.

Thanks.
0
 
LVL 20

Expert Comment

by:Madshi
ID: 1349462
Or is it this what you want? It's the fastest way I can think of...

function LoadStrFromFile(filename: string; var str: string) : boolean;
var s1 : TFileStream;
begin
  result:=false;
  if not fio_FileExists(filename) then exit;
  s1:=TFileStream.Create(filename,fmOpenRead or fmShareDenyNone);
  try
    SetLength(str,s1.Size);
    s1.Read(PChar(str)^,s1.Size);
  finally s1.Free end;
  result:=true;
end;

Regards, Madshi.
0
 
LVL 17

Accepted Solution

by:
inthe earned 20 total points
ID: 1349463
as awnser:
var
mystring:tstringlist;
begin
mystring:=tstringlist.create;
mystring.loadfromfile('c:\autoexec.bat');
{do whatever with your string}
end

Barry
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

A lot of questions regard threads in Delphi.   One of the more specific questions is how to show progress of the thread.   Updating a progressbar from inside a thread is a mistake. A solution to this would be to send a synchronized message to the…
Introduction I have seen many questions in this Delphi topic area where queries in threads are needed or suggested. I know bumped into a similar need. This article will address some of the concepts when dealing with a multithreaded delphi database…
Video by: Mark
This lesson goes over how to construct ordered and unordered lists and how to create hyperlinks.
Learn how to create flexible layouts using relative units in CSS.  New relative units added in CSS3 include vw(viewports width), vh(viewports height), vmin(minimum of viewports height and width), and vmax (maximum of viewports height and width).

920 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

11 Experts available now in Live!

Get 1:1 Help Now