asked on

Finding associated program..

You know when we double-click a file in the explorer, it finds the associated application, runs it, and gives the file as an argument to the app.

I know that it uses the information under HKEY_CLASSES_ROOT. But when I want to do the same thing in a Delphi program, everything goes well with 98 or 95 but there are problems while running on NT...(may be beacuse of user rights..)

How can I read these values while I am logged on as user not an administrator..

Thanx.

simonet

Can you give us a more detailed description of the problem under Windows NT?

How did you create the file association for your application's file type?

Alex
Athena's Place: http://www.bhnet.com.br/~simonet

philipleighs

You can use FindExecutable.

Cheers,
Phil.

itamar

Hi,

I couldn´t get where is the problem. In the file association, in getting the ParamStr parameter, etc...

Could you give more details ?

Thanks,
Itamar

philipleighs

If you want to use the registry instead of FindExecutable, then use TRegistry.OpenKeyReadOnly instead of TRegistry.OpenKey.

(You need D4).

OpenKeyReadOnly works on HKEY_LOCAL_MACHINE if you are a guest on NT. OpenKey(..., false) does not!

simonet

I still don't understand what you're trying to achieve. If you want to run a file/open using its default application, use ShellExecute or ShellExecuteEx. If you want to know the description of the file type associated with a certain extension, you can use SHGetFileInfo.

I still don't see why you'd need the Registry for any of these tasks. Do you mind explaining what exactly you're trying to do?

Alex
Athena's Place: http://www.bhnet.com.br/~simonet

Madshi

Alex is right. If possible, you should use ShellExecute(Ex). If you really want to KNOW which exe belongs to a specific file, you can use this one (Phil already suggested it):

uses shellAPI;

function FindExecutable(filename: string) : string;
var arrch : array [0..MAX_PATH] of char;
begin
if shellAPI.FindExecutable(pchar(ExtractFileName(filename)),pchar(ExtractFilePath(filename)),arrch)>32 then
result:=arrch
else result:=filename;
end;

Regards, Madshi.

BoRiS

new_x

Here is a way to do under all platforms(it's form the borland site)...

uses
{$IFDEF WIN32}
Registry; {We will get it from the registry}
{$ELSE}
IniFiles; {We will get it from the win.ini file}
{$ENDIF}

{$IFNDEF WIN32}
const MAX_PATH = 144;
{$ENDIF}

function GetProgramAssociation (Ext : string) : string;
var
{$IFDEF WIN32}
reg: TRegistry;
s : string;
{$ELSE}
WinIni : TIniFile;
WinIniFileName : array[0..MAX_PATH] of char;
s : string;
{$ENDIF}
begin
{$IFDEF WIN32}
s := '';
reg := TRegistry.Create;
reg.RootKey := HKEY_CLASSES_ROOT;
if reg.OpenKey('.' + ext + '\shell\open\command',
false) <> false then begin
{The open command has been found}
s := reg.ReadString('');
reg.CloseKey;
end else begin
{perhaps thier is a system file pointer}
if reg.OpenKey('.' + ext,
false) <> false then begin
s := reg.ReadString('');
reg.CloseKey;
if s <> '' then begin
{A system file pointer was found}
if reg.OpenKey(s + '\shell\open\command',
false) <> false then
{The open command has been found}
s := reg.ReadString('');
reg.CloseKey;
end;
end;
end;
{Delete any command line, quotes and spaces}
if Pos('%', s) > 0 then
Delete(s, Pos('%', s), length(s));
if ((length(s) > 0) and
(s[1] = '"')) then
Delete(s, 1, 1);
if ((length(s) > 0) and
(s[length(s)] = '"')) then
Delete(s, Length(s), 1);
while ((length(s) > 0) and
((s[length(s)] = #32) or
(s[length(s)] = '"'))) do
Delete(s, Length(s), 1);
{$ELSE}
GetWindowsDirectory(WinIniFileName, sizeof(WinIniFileName));
StrCat(WinIniFileName, '\win.ini');
WinIni := TIniFile.Create(WinIniFileName);
s := WinIni.ReadString('Extensions',
ext,
'');
WinIni.Free;
{Delete any command line}
if Pos(' ^', s) > 0 then
Delete(s, Pos(' ^', s), length(s));
{$ENDIF}
result := s;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
ShowMessage(GetProgramAssociation('gif'));
end;

Later
BoRiS

philipleighs

One thing about FindExecutable is that it can only be used on files that exist.

You can't do this:
FindExecutable(..., '*.hcp', ...)
It will fail.

So if you're writing a WinZip style program then FindExecutable will be no good to you.

Maybe this little tidbit will save you some time going through all the options.

Cheers,
Phil.

Madshi

Hi Phil, I noticed one strange thing: FindExecutable works NOT with "*.bmp", but it works well with "*.txt" on my computer. That's quite strange, isn't it!?

Regards, Madshi.

philipleighs

Yeah, that is wierd.
I tried it on mine, neither *.bmp nor *.txt worked!
>>
SetLength(s, MAX_PATH);
if FindExecutable('*.bmp', nil, PChar(s)) > 32 then
ShowMessage(PChar(s));
<<

Maybe SHGetFileInfo does a better job.
I haven't tried.

Cheers,
Phil.

itamar

new_x

Helloooo !!!!

nrico

Maybe "*.txt" did work but "*.bmp" not because in there current directory there WAS a file with the .txt extension but there WASN'T any with ".bmp". Just a thought.

Rico

Madshi

Rico, yep, sounds logical...

new_x

ASKER

Hi al

I want to asscociate my own program with a file extension, To do that I think I have to write some data under HKEY_CLASSES root, so then when somebody clicks a file of with that extension myprogram will run.

For instance I want to make 'tlx' extension associated with my App, so to make this change I have to create the key HKEY_CLASSES_ROOT\.tlx and write some data under it . For intance in my registry under HKEY_CLASSES _ROOT there is a key
.bmp , under this key the string (default) 'ACDC_BMP ' exists.
There is also another key with the name ACDC_BMP.
Under ACDC_BMP\Shell\open\command the associated app name exists.
But under NT, there are some restrictions when you read/write to registry . Am I wrong..

Thanx..

ASKER CERTIFIED SOLUTION

simonet

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new_x

ASKER

I Thank you all

new_x

ASKER

I Thank you all