Find Directories in path and put in TStringList

[nugax]

I am trying to find all directories in a path and put them in a TString list. I have the below code but it is giving me an access violation.

Code: Pascal  [Select][+][-]

1. /Get Directories As TStringList
2. function GetDirs(sPath: string): TStringList;
3. var
4.   Info: TSearchRec;
5.   Count: longint;
6.   TReturnString: TStringList;
7.  
8. begin
9.   Count := 0;
10.  
11.   TReturnString := TStringList.Create;
12.   if FindFirst(sPath + '/*', faAnyFile, Info) = 0 then
13.   begin
14.  
15.     repeat
16.       //Inc(Count);
17.       with Info do
18.       begin
19.         if (Attr and faDirectory) = faDirectory then
20.           TReturnString.Add(info.Name);
21.         //Writeln(Name: 40, Size: 15);
22.       end;
23.     until FindNext(info) <> 0;
24.     FindClose(Info);
25.   end;
26.  
27. end;    

[engkin]

Use Result instead of TReturnString

[nugax]

I dont understand where to use result. You mean create a TStringList locally and return in with result := MyTStringList; ?

[Jorg3000]

This is my procedure to this subject ...
Here the StringList must be created outside the function by the caller. This has the advantage that it is clear to the caller that he must take care of the StringList (create and destroy).

Code: Pascal  [Select][+][-]

1. function readSubFolderNames(const aPath: String; sl: TStringList): Integer;  // Result = -1 or Number of folders found
2. var
3.     sr: TSearchRec;
4.     Mask: String;
5. begin
6.   if (aPath='') or (sl=nil) then Exit(-1);
7.   if not DirectoryExists(aPath) then Exit(-1);
8.  
9.   Result:=0;  // Number of folders found
10.   Mask:=IncludeTrailingPathDelimiter(aPath)+'*.*';
11.  
12.   initialize(sr); FillChar(sr,SizeOf(sr),0);
13.  
14.   if SysUtils.FindFirst(Mask,faDirectory,sr)=0 then
15.    Repeat
16.      if sr.Attr AND faDirectory=0 then Continue;
17.      if (sr.Name='') or (sr.Name='.') or (sr.Name='..') then Continue;
18.      inc(Result);
19.      sl.Add(sr.Name);
20.    Until SysUtils.FindNext(sr)<>0;
21.  
22.   SysUtils.FindClose(sr);
23. end;
24.  

[nugax]

Nice code! Ill try it out.

[nugax]

Below is my code. I used your code exactly. I am getting index 0 out of bounds...  I confirmed the given path is correct...

Code: Pascal  [Select][+][-]

1. //Start MRC Multiplexer
2. class function mrcMultiPlexer.StartMRC() : string;
3. var
4.   sInput: string;
5.   sOutput: string;
6.   boolRun: integer;
7.   sPId: integer;
8.   sData: string;
9.   F: textfile;
10.   sFileName : string;
11.   TDirList : TStringList;
12.   iNumbdir : integer;
13.  
14. begin
15.   CyberMRCMultiPlexer := TIdTCPClient.Create;
16.   CyberMRCMultiPlexer := IdTCPClient.TIdTCPClient.Create;
17.   CyberMRCMultiPlexer.Port := programinfo.cbbsServicesIni.Mrc_Port.ToInteger;
18.   CyberMRCMultiPlexer.Host := programinfo.cbbsServicesIni.Mrc_Server_Hostname;
19.   CyberMRCMultiPlexer.Connect;
20.  
21.   boolRun := 1;
22.  
23.   sOutput := self.SendHandshake();
24.   if (sOutPut = 'SERVER~~~~~~HELLO~') then
25.   begin
26.     logging.WriteCBBSLog('MRC: Handshake complete with server');
27.  
28.     sPId := baseunix.FpFork;
29.     if (sPID > 0) then
30.     begin
31.       logging.WriteCBBSLog('MRC: Connected to server');
32.       exit(sPId.ToString);
33.     end;
34.  
35.     repeat
36.       sData := CyberMRCMultiPlexer.IOHandler.ReadLn();
37.       if (sData = 'SERVER~~~CLIENT~~~ping~') then
38.       begin
39.         self.SendMsg('CLIENT~' + programinfo.cbbsMRC.sBBSName + '~~SERVER~ALL~~IMALIVE:' + programinfo.cbbsMRC.sBBSName + ' ~');
40.       end;
41.  
42.  
43.  
44.       //Check For Ping And Reply
45.       if (sData <> '') Then
46.       begin
47.        // write(sData + ' ');
48.               end;
49.  
50.       if (sData <> '') Then
51.       begin
52.       sFileName := 'mess-' + random(99999).tostring + '.mrc';
53.       TDirList := TStringList.Create;
54.       //Load Directory List
55.       iNumbdir:=cyberio.readSubFolderNames(programinfo.cbbsInfo.sSessionsDir, TDirList);
56.  
57.  
58.       write('dir: ' + TDirList.Strings[0]);
59.  
60.  
61.       end;
62.       sData := '';
63.     until (boolRun = 0);
64.  
65.   end;
66.  
67. end;
68.  
69.                

[



quote author=Jorg3000 link=topic=58473.msg435458#msg435458 date=1645852606]
This is my procedure to this subject ...
Here the StringList must be created outside the function by the caller. This has the advantage that it is clear to the caller that he must take care of the StringList (create and destroy).

Code: Pascal  [Select][+][-]

1. function readSubFolderNames(const aPath: String; sl: TStringList): Integer;  // Result = -1 or Number of folders found
2. var
3.     sr: TSearchRec;
4.     Mask: String;
5. begin
6.   if (aPath='') or (sl=nil) then Exit(-1);
7.   if not DirectoryExists(aPath) then Exit(-1);
8.  
9.   Result:=0;  // Number of folders found
10.   Mask:=IncludeTrailingPathDelimiter(aPath)+'*.*';
11.  
12.   initialize(sr); FillChar(sr,SizeOf(sr),0);
13.  
14.   if SysUtils.FindFirst(Mask,faDirectory,sr)=0 then
15.    Repeat
16.      if (sr.Name='.') or (sr.Name='..') then Continue;
17.      inc(Result);
18.      sl.Add(sr.Name);
19.    Until SysUtils.FindNext(sr)<>0;
20.  
21.   SysUtils.FindClose(sr);
22. end;
23.  

[/quote]

[Jorg3000]

Sorry, I forgot this line

Code: Pascal  [Select][+][-]

1. if sr.Attr AND faDirectory=0 then Continue;

Updated my example above.
It's working at my computer (Windows).

[dbannon]

Might be worth noting the help text for FindFirst, put cursor on the FindFirst statement and press F1.

It warns you against assuming that setting attr to (eg) faDirectory will get only directories back. You get back ordinary files AND, in this case directories.

So, Jorg3000 code might need to look a bit like this (untested) -

Code: Pascal  [Select][+][-]

1.     ...
2.     if FindFirst(AppendPathDelim(APath) + '*',faDirectory, SR) = 0 then begin
3.         try
4.             repeat
5.                 if ((SR.Attr and faDirectory) = faDirectory) and (ST>Name <> '.') and (SR.Name <> '..') then
6.                          SL.Add(SR.Name);    
7.             until FindNext(Info) <> 0;
8.         finally
9.             FindClose(Info);
10.         end;
11.     end;

The TSearchRecord does not need to be initialized or filled in, that happens in FindFirst.

On the other hand, creating the the stringlist up in the calling function as shown is really good. Creating in a function and then passing it back up stream is very bad practice that will, sooner or later lead to a memory leak.

edit:typo

Davo

[Jorg3000]

nugax, in your code you have to check if there is a String at Index 0

Code: Pascal  [Select][+][-]

1. iNumbdir:=cyberio.readSubFolderNames(programinfo.cbbsInfo.sSessionsDir, TDirList);
2.  
3. if iNumbdir>0 then write('dir: ' + TDirList.Strings[0]);
4.  

[Jorg3000]

dbannon, the Try ... Finally in your code is a good idea!

But especially the functions FindFirst and FindNext do not contain any Exception generation.
Nevertheless, Try ... Finally ist good and right of course! 

[loaded]

Let's give an example that shows the folder browsing in tree view.

[bytebites]

Code: Pascal  [Select][+][-]

1. write('dir: ' + TDirList.Strings[0]);

Coding style issue: Don't prefix variable name with T-letter.

[nugax]

I added your code but it still isnt finding anything. Im on linux.

nugax, in your code you have to check if there is a String at Index 0

Code: Pascal  [Select][+][-]

1. iNumbdir:=cyberio.readSubFolderNames(programinfo.cbbsInfo.sSessionsDir, TDirList);
2.  
3. if iNumbdir>0 then write('dir: ' + TDirList.Strings[0]);
4.  

[Jorg3000]

Is sSessionsDir definied and does that folder exist?

Code: Pascal  [Select][+][-]

1. write(programinfo.cbbsInfo.sSessionsDir);
2. write(IntToStr(iNumbdir));
3.  

[jamie]

https://wiki.freepascal.org/FindAllFiles


That won't do?