how to start aplication on system startup

Code for building the statup shortcut link automatically. It uses the applications title, filename, and icon to build the link.

HTH,
Russell

////////////////////////////////////////////////////////////////////////////////
//
//   Function    :  AddSelfStartup
//
//   Parameters  :
//                     AllUsers -  Boolean value indicating if this should apply
//                     to all users, or only the current user
//
//   Returns     :  HResult status of the IShellLink handling. On success S_OK
//                  will be returned.
//
//   Notes       :  Routine expects the following units in the uses clause:
//
//                     Forms, ComObj, ActiveX, ShlObj
//
//                  Forms is required for access to the Application instance,
//                  and the latter are required for the COM functionality.
//
/////////////////////////////////////////////////////////////////////////////////
function AddSelfStartup(AllUsers: Boolean = False): HResult;

  function CheckSetStatus(CheckStatus: HResult; out SetStatus: HResult): Boolean;
  begin
     // Resource protection
     try
        // Set outbound status
        SetStatus:=CheckStatus;
     finally
        // Determine if this was a success
        result:=Succeeded(CheckStatus);
     end;
  end;

var
  lpwszPath:        Array [0..MAX_PATH] of WideChar;
  lpszPath:         Array [0..MAX_PATH] of Char;
  pvFile:           IPersistFile;
  pvLink:           IShellLink;
  dwPath:           DWORD;
const
  STARTUP_PATH      =  '%s\Start Menu\Programs\Startup\';
begin

  // Initialize the com library
  if CheckSetStatus(CoInitialize(nil), result) then
  begin
     // Resource protection
     try
        // Attempt to create instance of shell link
        if CheckSetStatus(CoCreateInstance(CLSID_ShellLink, nil, CLSCTX_INPROC_SERVER, IShellLink, pvLink), result) then
        begin
           // Resource protection
           try
              // Get the executable filename (null terminate result)
              lpszPath[GetModuleFileName(0, @lpszPath, MAX_PATH)]:=#0;
              // Update the link settings
              if CheckSetStatus(pvLink.SetPath(@lpszPath), result) and CheckSetStatus(pvLink.SetIconLocation(@lpszPath, 0), result) then
              begin
                 // Set the description (don't care about status)
                 pvLink.SetDescription(PChar(Application.Title));
                 // Query for IPersistFile
                 if CheckSetStatus(pvLink.QueryInterface(IPersistFile, pvFile), result) then
                 begin
                    // Resource protection
                    try
                       // Determine if current user or all users
                       if AllUsers then
                          // Expand the path
                          dwPath:=ExpandEnvironmentStrings(PChar(Format(STARTUP_PATH, ['%ALLUSERSPROFILE%'])), lpszPath, SizeOf(lpszPath))
                       else
                          // Expand the path
                          dwPath:=ExpandEnvironmentStrings(PChar(Format(STARTUP_PATH, ['%USERPROFILE%'])), lpszPath, SizeOf(lpszPath));
                       // Concat the application filename with the extension of .lnk
                       StrLCat(@lpszPath, PChar(ChangeFileExt(ExtractFileName(Application.ExeName), '.lnk')), MAX_PATH);
                       // Convert to wide char
                       MultiByteToWideChar(CP_ACP, 0, @lpszPath, -1, @lpwszPath, MAX_PATH);
                       // Save to file
                       result:=pvFile.Save(@lpwszPath, True);
                    finally
                       // Release the interface
                       pvFile:=nil;
                    end;
                 end;
              end;
           finally
              // Release the interface
              pvLink:=nil;
           end;
        end;
     finally
        // Uninit the com library
        CoUninitialize;
     end;
  end;

end;

----

  // Example usage
  AddSelfStartup(True);
 

It depends on the accessability level that the developer wishes to expose to the user. There is no right / wrong way, it just depends on the intent. If you wish to make it easy for your user to control (remove) a startup item, then placing it in the startup folder makes sense. If you wish to keep the novice user from modifying the startup of your program, then the registry makes sense.

Russell

// Example using registry
function AddRegSelfStartup(AllUsers: Boolean = False): Integer;

  function CheckSetStatus(CheckStatus: Integer; out SetStatus: Integer): Boolean;
  begin
     // Resource protection
     try
        // Set outbound status
        SetStatus:=CheckStatus;
     finally
        // Determine if this was a success
        result:=(CheckStatus = ERROR_SUCCESS);
     end;
  end;

var
  hkBase:           HKEY;
  hkRun:            HKEY;
  dwDisp:           DWORD;
begin

  // Check key to open
  if AllUsers then
     // Use local machine key
     hkBase:=HKEY_LOCAL_MACHINE
  else
     // Use current user key
     hkBase:=HKEY_CURRENT_USER;

  // Attempt to create / open the key
  if CheckSetStatus(RegCreateKeyEx(hkBase, 'Software\Microsoft\Windows\CurrentVersion\Run', 0, nil, REG_OPTION_NON_VOLATILE, KEY_WRITE, nil, hkRun, @dwDisp), result) then
  begin
     // Resource protection
     try
        // Set the value (account for null as well)
        result:=RegSetValueEx(hkRun, PChar(ExtractFileName(Application.ExeName)), 0, REG_SZ, PChar(Application.ExeName), Succ(Length(Application.ExeName)));
     finally
        // Close the key
        RegCloseKey(hkRun);
     end;
  end;

end;

Programmatically Edit Registry to Run Your Delphi Application on Windows Startup
By programmatically editing the Windows Registry, using the TRegistry object, you can you can "automagically" start programs whenever Windows launches.
The procedure you can use to force "auto-run-on-Windows-startup" for your application might look like:

procedure RunOnStartup(const sCmdLine: string; bRunOnce: boolean = false; Remove: Boolean = false) ;
var
  sKey: string;
  Section: string;
const
  ApplicationTitle = Your Application TITLE;
begin
  if (bRunOnce) then
    sKey := 'Once'
  else
    sKey := '';

  Section := 'Software\Microsoft\Windows\CurrentVersion\Run' + sKey + #0;

  with TRegIniFile.Create('') do
    try
      RootKey := HKEY_LOCAL_MACHINE;
      if Remove then
        DeleteKey(Section, ApplicationTitle)
      else
        WriteString(Section, ApplicationTitle, sCmdLine) ;
    finally
      Free;
    end;
end;

On Vista, if the user running the application does not have admin rights the above code would fail, due to UAC!