Get a list of all indexed files in Windows with Delphi - windows

Question

I would like to list all the files that windows has indexed using its Windows Indexing Service.
Specified file extensions are acceptable.
For instance: I am working an a software which presents user media such as photos and videos. I am currently using the following custom procedure to find the files myself:
function FindAllFiles_Safe(aDirectory, aFilter: string; aIncludeSubDirs: boolean): string;
{$IFDEF DCC}
var TD: TDirectory;
SO: TSearchOption;
DF: TStringDynArray;
i: integer;
sl: TStringList;
MaskArray: TStringDynArray;
Predicate: TDirectory.TFilterPredicate;
{$ENDIF}
begin
{$IFDEF FPC}
result:=FindAllFiles(aDirectory,aFilter,aIncludeSubDirs).text;
{$ENDIF}
{$IFDEF DCC}
MaskArray := SplitString(aFilter, ';');
if aIncludeSubDirs=true then SO:=TSearchOption.soAllDirectories;
Predicate :=
function(const Path: string; const SearchRec: TSearchRec): Boolean
var Mask: string;
begin
for Mask in MaskArray do
if MatchesMask(SearchRec.Name, Mask) then
exit(True);
exit(False);
end;
//DF:=TD.GetFiles(aDirectory, Predicate, SO);
DF:=TD.GetFiles(aDirectory, SO, Predicate);
if length(DF)=0 then exit;
sl:=TStringList.Create;
for i := 0 to length(DF)-1 do sl.Add(DF[i]);
result:=sl.Text;
sl.Free;
{$ENDIF}
end;
Is there a way to access files that Windows has already indexed?
I'd like to take advantage of Windows Indexing Service to quickly retrieve files, rather then wasting resources if Windows already has done it before.

Answer 1

One of the ways to query the index of the Windows Search is use ADO and the Query Syntax (AQS) and SQL.
Try this sample code (off course you can improve the SQL sentence to filter and speed up the results)
{$APPTYPE CONSOLE}
{$R *.res}
uses
ADOInt,
SysUtils,
ActiveX,
ComObj,
Variants;
procedure QuerySystemIndex;
var
Connection : _Connection;
RecordSet: _RecordSet;
v: Variant;
begin;
OleCheck(CoCreateInstance(CLASS_Connection, nil, CLSCTX_ALL, IID__Connection, Connection));
OleCheck(CoCreateInstance(CLASS_RecordSet, nil, CLSCTX_ALL, IID__RecordSet, RecordSet));
Connection.CursorLocation := adUseClient;
Connection.Open('Provider=Search.CollatorDSO;Extended Properties=''Application=Windows'';', '', '', adConnectUnspecified);
Recordset.Open('SELECT Top 5 System.ItemPathDisplay FROM SYSTEMINDEX', Connection, adOpenForwardOnly, adLockReadOnly, adCmdText);
Recordset.MoveFirst;
v:='System.ItemPathDisplay';
while not Recordset.EOF do
begin
Writeln(Recordset.Fields.Item[v].Value);
Recordset.MoveNext();
end;
end;
begin
try
CoInitialize(nil);
try
QuerySystemIndex;
finally
CoUninitialize;
end;
except
on E:EOleException do
Writeln(Format('EOleException %s %x', [E.Message,E.ErrorCode]));
on E:Exception do
Writeln(E.Classname, ':', E.Message);
end;
Writeln('Press Enter to exit');
Readln;
end.
You can found alternatives ways to access the Search Index on the MSDN documentation.

Answer 2

There is an API for Windows Search (previously known as Windows Desktop Search).
However, whilst the Windows Search API is undoubtedly enormously powerful, I think for simply locating files based on file extension (or even other constituent elements in the file name) the Windows Search API is likely to prove prohibitively complex and provide negligible benefit, unless you are dealing with a truly extraordinary number of files.