Here is a method for retrieving a list of installed applications on a particular machine running a Windows OS.

Problem/Question/Abstract:

Here is a method for retrieving a list of installed applications on a particular machine running a Windows OS.

Answer:

1. Start up Delphi.
2. Select File | New Application.
3. Add Registry to the uses of your new Unit.
4. Place a TListBox (ListBox1) component on your form.
5. Place a TButton (Button1) in your form.
6. Place the following code in the OnClick event of the Button1:

~~~~~~~~~~~~~~~~~~~~~~~~~
procedure TForm1.Button1Click(Sender: TObject) ;
const
REGKEYAPPS = '\SOFTWARE\Microsoft\Windows\
CurrentVersion\Uninstall';

var
reg : TRegistry;
List1 : TStringList;
List2 : TStringList;
j, n : integer;

begin
reg := TRegistry.Create;
List1 := TStringList.Create;
List2 := TStringList.Create;

{Load all the subkeys}
with reg do
begin
RootKey := HKEY_LOCAL_MACHINE;
OpenKey(REGKEYAPPS, false) ;
GetKeyNames(List1) ;
end;
{Load all the Value Names}
for j := 0 to List1.Count -1 do
begin
reg.OpenKey(REGKEYAPPS + '' + List1.Strings[j],false) ;
reg.GetValueNames(List2) ;

{We will show only if there is 'DisplayName'}
n := List2.IndexOf('DisplayName') ;
if (n <> -1) and
(List2.IndexOf('UninstallString') <> -1) then
begin
ListBox1.Items.Add(
(reg.ReadString(List2.Strings[n]))) ;
end;
end;
List.Free;
List2.Free;
reg.CloseKey;
reg.Destroy;
end;