Difference between revisions of "FindAllFiles"

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m (FileUtils -> FileUtil)
m (Fixed syntax highlighting; fixed wiki markup)
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* http://lazarus-ccr.sourceforge.net/docs/lcl/fileutil/tfilesearcher.html
 
* http://lazarus-ccr.sourceforge.net/docs/lcl/fileutil/tfilesearcher.html
  
<syntaxhighlight>
+
<syntaxhighlight lang="pascal">
 
procedure FindAllFiles(AList: TStrings; const SearchPath: String;
 
procedure FindAllFiles(AList: TStrings; const SearchPath: String;
 
   SearchMask: String = ''; SearchSubDirs: Boolean = True; DirAttr: Word = faDirectory);  
 
   SearchMask: String = ''; SearchSubDirs: Boolean = True; DirAttr: Word = faDirectory);  
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The second one is a '''[[Function|function]]''' which creates the stringlist internally and returns it as a function result. In both cases the stringlist must be destroyed by the calling procedure.
 
The second one is a '''[[Function|function]]''' which creates the stringlist internally and returns it as a function result. In both cases the stringlist must be destroyed by the calling procedure.
  
'''Example:'''
+
== Example ==
<syntaxhighlight>
+
 
 +
<syntaxhighlight lang="pascal">
 
uses  
 
uses  
 
   ..., FileUtil, ...
 
   ..., FileUtil, ...
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The ''function'' "FindAllFiles" creates the stringlist internally. This may look very convenient at first sight, but it is very easy to create '''memory leaks''' that way:
 
The ''function'' "FindAllFiles" creates the stringlist internally. This may look very convenient at first sight, but it is very easy to create '''memory leaks''' that way:
  
<syntaxhighlight>
+
<syntaxhighlight lang="pascal">
 
   // DON'T EVER DO THIS !!!! - There is no way to destroy the stringlist created by FindAllFiles.
 
   // DON'T EVER DO THIS !!!! - There is no way to destroy the stringlist created by FindAllFiles.
 
   Listbox1.Items.Assign(FindAllFiles(LazarusDirectory, '*.pas;*.pp;*.p;*.inc', true);
 
   Listbox1.Items.Assign(FindAllFiles(LazarusDirectory, '*.pas;*.pp;*.p;*.inc', true);

Revision as of 01:38, 4 February 2020

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Unit: Lazarus fileutil

See also:

procedure FindAllFiles(AList: TStrings; const SearchPath: String;
  SearchMask: String = ''; SearchSubDirs: Boolean = True; DirAttr: Word = faDirectory); 

function FindAllFiles(const SearchPath: String; SearchMask: String = '';
  SearchSubDirs: Boolean = True): TStringList;

FindAllFiles looks for files matching the searchmask in the SearchPath directory and if specified its children and populates a stringlist with the resulting filenames.

The mask can be a single mask like you can use with the FindFirst/FindNext functions, or it can consist of a list of masks, separated by a semicolon (;).
Spaces in the mask are treated as literals.

There are two overloaded versions of this routine. The first one is a procedure and assumes that the receiving stringlist already has been created. The second one is a function which creates the stringlist internally and returns it as a function result. In both cases the stringlist must be destroyed by the calling procedure.

Example

uses 
  ..., FileUtil, ...
var
  PascalFiles: TStringList;
begin
  PascalFiles := TStringList.Create;
  try
    FindAllFiles(PascalFiles, LazarusDirectory, '*.pas;*.pp;*.p;*.inc', true); //find e.g. all pascal sourcefiles
    ShowMessage(Format('Found %d Pascal source files', [PascalFiles.Count]));
  finally
    PascalFiles.Free;
  end;

// or

begin
  //No need to create the stringlist; the function does that for you
  PascalFiles := FindAllFiles(LazarusDirectory, '*.pas;*.pp;*.p;*.inc', true); //find e.g. all pascal sourcefiles
  try
    ShowMessage(Format('Found %d Pascal source files', [PascalFiles.Count]));
  finally
    PascalFiles.Free;
  end;

IMPORTANT NOTE: The function "FindAllFiles" creates the stringlist internally. This may look very convenient at first sight, but it is very easy to create memory leaks that way:

  // DON'T EVER DO THIS !!!! - There is no way to destroy the stringlist created by FindAllFiles.
  Listbox1.Items.Assign(FindAllFiles(LazarusDirectory, '*.pas;*.pp;*.p;*.inc', true);
Light bulb  Note: If you want to use this function in command line programs, add a project requirement for LCLBase, which will not pull in the entire LCL