Some old, but useful code

Digging through some archives, I found some useful code, so I thought I would share these.

These snippets are from my Delphi programming days, so the code is in Pascal, but it can easily be converted to whichever language is being used.

Hide an application from the taskbar - Delphi

This is a really simple technique that can hide your application from the taskbar.In your main forms On Create event, type the following code:

SetWindowLong(Application.Handle, GWL_EXSTYLE, GetWindowLong(Application.Handle, GWL_EXSTYLE ) or WS_EX_TOOLWINDOW and not WS_EX_APPWINDOW);

That's all there is to it.

Making a program run at Windows startup - Delphi

On your programs Settings or Preferences form, place a TCheckBox with the caption Run at Windows Startup.

In the forms uses clause, include the unit Registry.

In the TCheckBox On Click event, include the following code:

procedure TForm1.TCheckBox1Click(Sender: TObject); 

     var Registry: TRegistry; 

 begin

      Registry := TRegistry.Create; 

      Registry.RootKey := HKEY_LOCAL_MACHINE;

      Registry.OpenKey('Software\Microsoft\Windows\CurrentVersion\Run', false);

      If TCheckBox1.Checked then 

          Registry.WriteString(Application.Title, Application.ExeName) 

      else Registry.DeleteValue(Application.Title); 

      Registry.CloseKey; 

      Registry.free; 

end; 

To ensure that the TCheckBox displays the current status of the function when the form is displayed, we need to insert the following code into the forms On Show event: 

procedure TForm1.FormShow(Sender: TObject); 

    var Registry : TRegistry; 

begin 

    Registry := TRegistry.Create;

    Registry.RootKey := HKEY_LOCAL_MACHINE;

    Registry.OpenKey('Software\Microsoft\Windows\CurrentVersion\Run', false); 

    CheckBox1.Checked := Registry.ValueExists(Application.Title); 

    Registry.CloseKey; 

    Registry.free; 

end;

This code simply checks to see if the run command for the appllication has been inserted into the registry. If it has, the the TCheckBox is checked, otherwise it is not.