asked on

Can you help me get streamed data from the net into an array?

I am writing some code that pulls data from a small file on my website
http://www.gurlpages.com/computer/gwena/testdata.txt
I found a free component package by a guy named Hoerstemeier
that seems to work ok but all I can manage to do is get the data into a Tmemo box :(
I need to get this data into an array where I can do something with it.... here is the code
I have written that manages to get the data into the memo box

unit httpmain;

interface

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

type

TForm1 = class(TForm)
HTTP: T_HTTP;
Memo: TMemo;
btn_doit: TButton;
procedure btn_doitClick(Sender: TObject);
end;
var
Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.btn_doitClick(Sender: TObject);

begin
http.url:= 'http://www.gurlpages.com/computer/gwena/testdata.txt';
http.Authorization:='';
http.action;
memo.lines.loadfromstream(http.stream);
end;

end.

----------------------------

So how in the world can you get this 'stream' data into a
array? And by the way how can you get the lines of text from a memo box into a string or an array??

I compiled a tiny exe file that pulls the testdata.txt file off my site and displays it .. it is here if you need to see it ...

http://www.gurlpages.com/computer/gwena/images/getdata.exe

By the way I'm using Delphi 2 standard to write this...

Gwena

ASKER

Edited text of question.

ASKER CERTIFIED SOLUTION

rwilson032697

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rwilson032697

Actually, to add some more to this, notice that it is the lines property doing the streaming? This means you can do this:

var
TheStrings : TStringList;

...
TheStrings.loadfromstream(http.stream);
...

Cheers,

Raymond.

viktornet

Let's see what Gwena's gonna say :)

Gwena

ASKER

Very Cool! :-)

OK.. I now have the code working just fine...I can use the data by doing the following...

var
WebData: Array[0..600] of string;

then later I....

memo.lines.loadfromstream(http.stream);
for i := 0 to memo.lines.count -1 do
WebData[i] := memo.lines[i];

Now I have the data I want to play with in my WebData string array :-)

When I try to do this without using a Tmemo I still have probs :(

var
TheStrings: TStringList;

Then later...

TheStrings.loadfromstream(http.stream);

When I do this I get an error that says 'access violation' ???
If the (TheStrings: TstringList;) is like an array of strings then do you think
that I am somehow attempting to access a nonexistant element of the array?
How do I set the array's size?
do I access elements of this array like this..
TheStrings[x] or does it have a property like the 'lines' in the Tmemo ??

I'm partway there...but still a bit clueless ;-)

viktornet

you can do something like this....

WebData: Array[0..600] of string[50];

Move((http.stream as TMemoryStream).Memory^, WebData^, stream.size);

something like that might do it :))

..-=ViKtOr=-..

Gwena

ASKER

I looked through all the help files about Tstringlist and tried the following which seems to work

var
TheStrings : TStringList;

then later

TheStrings := TStringList.Create;
TheStrings.loadfromstream(http.stream);

for i := 0 to 2 do
webdata[i] := TheStrings[i];
TheStrings.Free;

This works...but is it correct??? or will it lead to bugs later on?

plus...how do I determine how many elements there are in the TheStrings array?
I used memo.lines.count to find out how many strings had been loaded into the Tmemo .. is there a similar way to determine array size for TheStrings?

Gwena

ASKER

Ok... I think I have most of my problems solved now :)
I just used TheStrings.count to get the number of strings in the array... DUH... (wake up Gwena)
Thanx guys... now I will grade the answer :-)

rwilson032697

Gwena: Yes, you need to create the TStringlist - I didn't do that as I was really showing a skeleton with some context - sorry about that!

Of course, you can always jsut use the stringlist and not move the strings to an array (as strings (assuming you are using $H+ or ANSIStrings) are actually just pointers anyway, so an array of string is very close in structure to a stringlist).

Cheers,

Raymond.