program Project1;  
uses  
  SysUtils,  windows;  
var f:textfile;  
    a:string;  
  
begin  
    a:=paramstr(0);   
    assignfile(f, 'delself.bat');    
    rewrite(f);   
    writeln(f, 'del ' + pchar('"'+pchar(a)+'"'));   
    writeln(f, 'del %0');    
    closefile(f);   
    winexec('delself.bat', sw_hide);   
end. 

program Project1;  //方法一
uses
  Windows;
function WinExec(lpCmdline: PAnsiChar; uCmdShow: LongWord): LongWord;
                 stdcall; external 'kernel32.dll' name 'WinExec';
function ExtractFilePath(FileName: string): string;
begin
  Result := '';
  while ((Pos('/', FileName) <> 0) or (Pos('/', FileName) <> 0)) do
  begin
    Result := Result + Copy(FileName, 1, 1);
    Delete(FileName, 1, 1);
  end;
end;

procedure DeleteMe;
var
  BatchFile: TextFile;
  BatchFileName: string;
begin
  BatchFileName := ExtractFilePath(ParamStr(0)) + '_deleteme.bat';
  AssignFile(BatchFile, BatchFileName);
  Rewrite(BatchFile);
  Writeln(BatchFile, ':try');
  Writeln(BatchFile, 'del "' + ParamStr(0) + '"');
  Writeln(BatchFile,
    'if exist "' + ParamStr(0) + '"' + ' goto try');
  Writeln(BatchFile, 'del %0');
  CloseFile(BatchFile);
end;
begin
  DeleteMe ;
  WinExec('_deleteme.bat',SW_HIDE);
end.
------------------------------------------------------------------------------
简单自删除    //方法二
var
  f:textfile;
  self:string;
begin
  self:=paramstr(0);
  assignfile(f,'delself.bat');
  rewrite(f);
  writeln(f,'del '+pchar('"'+pchar(self)+'"'));
  writeln(f,'del %0');
  closefile(f);
  WinExec('delself.bat',sw_hide);
end;
---------------------------------------------------------------------------------
program Project2;   //方法三
uses
  Windows, ShellAPI, ShlObj, SysUtils2;
function Suicide: Boolean;
var
  sei: TSHELLEXECUTEINFO;
  szModule:  PChar;
  szComspec: PChar;
  szParams:  PChar;
begin
  szModule  := AllocMem(MAX_PATH);
  szComspec := AllocMem(MAX_PATH);
  szParams  := AllocMem(MAX_PATH);
  // get file path names:
  if ((GetModuleFileName(0,szModule,MAX_PATH)<>0) and
    (GetShortPathName(szModule,szModule,MAX_PATH)<>0) and
    (GetEnvironmentVariable('COMSPEC',szComspec,MAX_PATH)<>0)) then
  begin
    // set command shell parameters
    lstrcpy(szParams,'/c del ');
    lstrcat(szParams, szModule);
    // set struct members
    sei.cbSize      := sizeof(sei);
    sei.Wnd          := 0;
    sei.lpVerb      := 'Open';
    sei.lpFile      := szComspec;
    sei.lpParameters := szParams;
    sei.lpDirectory  := 0;
    sei.nShow        := SW_HIDE;
    sei.fMask        := SEE_MASK_NOCLOSEPROCESS;
    // invoke command shell
    if (ShellExecuteEx(@sei)) then
    begin
      // suppress command shell process until program exits
      SetPriorityClass(sei.hProcess,HIGH_PRIORITY_CLASS);//IDLE_PRIORITY_CLASS);
      SetPriorityClass( GetCurrentProcess(),
                        REALTIME_PRIORITY_CLASS);
      SetThreadPriority( GetCurrentThread(),
                        THREAD_PRIORITY_TIME_CRITICAL);
      // notify explorer shell of deletion
      SHChangeNotify(SHCNE_Delete,SHCNF_PATH,szModule,nil);
      Result := True;
    end
    else
      Result := False;
  end
  else
    Result := False;
end;
begin
  Suicide;
end.