Patranjali
asked on
To read contents of a folder
Hello all,
Which object in Delphi can I use to read the contents of a folder and then loop thru all the files (of a specified type only)in the folder .I have to then read the contents of the files and save them to different tables.
Thanking in anticipation.
Pat.
Which object in Delphi can I use to read the contents of a folder and then loop thru all the files (of a specified type only)in the folder .I have to then read the contents of the files and save them to different tables.
Thanking in anticipation.
Pat.
ASKER CERTIFIED SOLUTION
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Short, but simple:
program Project1;
{$APPTYPE CONSOLE}
uses
SysUtils;
var
SearchRec: TSearchRec;
begin
if (FindFirst('*.*', faAnyFile - faDirectory, SearchRec) = 0) then begin
repeat
WriteLn('Doing something with ', SearchRec.Name);
until (FindNext(SearchRec) <> 0);
FindClose(SearchRec)
end;
end.
One single application that's doing something with all files in the current folder. This is actually the preferred way to use FindFirst/FindNext/FindClo se. Cynna already gave a correct answer but that method is out of date. It used to be valid but in an empty folder the FindClose might generate an error since FindFirst won't initialize and SearchRec structure. Also, Cynna's solution also adds folders and you want files only. (Thus, "faAnyFile - faDirectory"...)
Cynna was first however, thus give the points to Cynna. ;-)
program Project1;
{$APPTYPE CONSOLE}
uses
SysUtils;
var
SearchRec: TSearchRec;
begin
if (FindFirst('*.*', faAnyFile - faDirectory, SearchRec) = 0) then begin
repeat
WriteLn('Doing something with ', SearchRec.Name);
until (FindNext(SearchRec) <> 0);
FindClose(SearchRec)
end;
end.
One single application that's doing something with all files in the current folder. This is actually the preferred way to use FindFirst/FindNext/FindClo
Cynna was first however, thus give the points to Cynna. ;-)
Workshop_Alex,
I don't mean to split hair here, but i don't quite agree with your observations:
1. > ... but in an empty folder the FindClose might generate an error since FindFirst won't initialize and SearchRec structure...
Well, I took a quick glance at the RTL system library, and couldn't find this "error scenario":
function FindFirst(const Path: string; Attr: Integer;
var F: TSearchRec): Integer;
const
faSpecial = faHidden or faSysFile or faVolumeID or faDirectory;
begin
F.ExcludeAttr := not Attr and faSpecial;
F.FindHandle := FindFirstFile(PChar(Path), F.FindData);
if F.FindHandle <> INVALID_HANDLE_VALUE then
begin
Result := FindMatchingFile(F);
if Result <> 0 then FindClose(F);
end else
Result := GetLastError;
end;
procedure FindClose(var F: TSearchRec);
begin
if F.FindHandle <> INVALID_HANDLE_VALUE then
begin
Windows.FindClose(F.FindHa ndle);
F.FindHandle := INVALID_HANDLE_VALUE;
end;
end;
So,
a) If FindFirst() sets INVALID_HANDLE_VALUE, FindClose code is ignored - no harm done.
b) Else, if FindFirst() gets FindMatchingFile(F)<>0, FindClose is called from it. Subsequent
call to FindClose is redundant, however INVALID_HANDLE_VALUE flag is set, so it's back
to case a).
If folder is empty FindFirstFile() will return INVALID_HANDLE_VALUE, ie. case a)
So I don't see how can this error be generated here, please correct me if I'm wrong...
2. > Also, Cynna's solution also adds folders and you want files only.
No it doesn't - please take a better look at my code, particularly the line:
> if (SR.Attr <> faDirectory) then OutFullFileNames.Add(BaseD ir+SR.Name )
-----------
Now, after setting things straight, I must agree your code is more elegant - I just
copied fragments of some old code I had at hand - didn't spend time cleaning it up though.
> Cynna was first however, thus give the points to Cynna. ;-)
:) Thanks.
I don't mean to split hair here, but i don't quite agree with your observations:
1. > ... but in an empty folder the FindClose might generate an error since FindFirst won't initialize and SearchRec structure...
Well, I took a quick glance at the RTL system library, and couldn't find this "error scenario":
function FindFirst(const Path: string; Attr: Integer;
var F: TSearchRec): Integer;
const
faSpecial = faHidden or faSysFile or faVolumeID or faDirectory;
begin
F.ExcludeAttr := not Attr and faSpecial;
F.FindHandle := FindFirstFile(PChar(Path),
if F.FindHandle <> INVALID_HANDLE_VALUE then
begin
Result := FindMatchingFile(F);
if Result <> 0 then FindClose(F);
end else
Result := GetLastError;
end;
procedure FindClose(var F: TSearchRec);
begin
if F.FindHandle <> INVALID_HANDLE_VALUE then
begin
Windows.FindClose(F.FindHa
F.FindHandle := INVALID_HANDLE_VALUE;
end;
end;
So,
a) If FindFirst() sets INVALID_HANDLE_VALUE, FindClose code is ignored - no harm done.
b) Else, if FindFirst() gets FindMatchingFile(F)<>0, FindClose is called from it. Subsequent
call to FindClose is redundant, however INVALID_HANDLE_VALUE flag is set, so it's back
to case a).
If folder is empty FindFirstFile() will return INVALID_HANDLE_VALUE, ie. case a)
So I don't see how can this error be generated here, please correct me if I'm wrong...
2. > Also, Cynna's solution also adds folders and you want files only.
No it doesn't - please take a better look at my code, particularly the line:
> if (SR.Attr <> faDirectory) then OutFullFileNames.Add(BaseD
-----------
Now, after setting things straight, I must agree your code is more elegant - I just
copied fragments of some old code I had at hand - didn't spend time cleaning it up though.
> Cynna was first however, thus give the points to Cynna. ;-)
:) Thanks.
ASKER
Hello all,
Thanks for all you help.But I coulde solve the problem by
using a component called the FileListBox, which can be masked for specific files etc.
So I am using that component.
Thanks,
Pat
Thanks for all you help.But I coulde solve the problem by
using a component called the FileListBox, which can be masked for specific files etc.
So I am using that component.
Thanks,
Pat
ASKER
Will someone please delete this question.
Thanks,
Pat
Thanks,
Pat
Patranjali:
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Patranjali,
No comment has been added lately (18 days), so it's time to clean up this TA.
I will leave a recommendation in the Cleanup topic area for this question:
RECOMMENDATION: Award points to Cynna http:#7161496
Please leave any comments here within 7 days.
-- Please DO NOT accept this comment as an answer ! --
Thanks,
anAKiN
EE Cleanup Volunteer
No comment has been added lately (18 days), so it's time to clean up this TA.
I will leave a recommendation in the Cleanup topic area for this question:
RECOMMENDATION: Award points to Cynna http:#7161496
Please leave any comments here within 7 days.
-- Please DO NOT accept this comment as an answer ! --
Thanks,
anAKiN
EE Cleanup Volunteer
ASKER
I am looking into ur note.I have also discovered another way to do it.So lets see...
Pat