procedure DeleteMe;
var
  BatchFile: TextFile;
  BatchFileName: string;
  ProcessInf TProcessInformation;
  StartUpInf TStartupInfo;
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);

  FillChar(StartUpInfo, SizeOf(StartUpInfo), $00);
  StartUpInfo.dwFlags := STARTF_USESHOWWINDOW;
  StartUpInfo.wShowWindow := SW_HIDE;
  if CreateProcess(nil, PChar(BatchFileName), nil, nil,
    False, IDLE_PRIORITY_CLASS, nil, nil, StartUpInfo,
    ProcessInfo) then
  begin
    CloseHandle(ProcessInfo.hThread);
    CloseHandle(ProcessInfo.hProcess);
  end;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  DeleteMe;
  close;
end;

end.

第二种：

类　别:系统控制
  我们经常遇到这样的软件,运行之后就消失的无影无踪,特别是一些黑客的木马工具。
  如果我们能掌握这个技术,即使不做黑客工具,也可以在程序加密、软件卸载等方面发挥作用。
  那么他们是怎样实现的呢？
---- 以delphi为例,在form关闭的时候执行以下函数closeme即可:
procedure TForm1.closeme;
var f:textfile;
begin
assignfile(f,'.\delme.bat');
rewrite(f);
writeln(f,'@echo off');
writeln(f,':loop');
writeln(f,'del "'+application.ExeName+'"');
writeln(f,'if exist .\file.exe goto loop');
writeln(f,'del .\delme.bat');
closefile(f);
winexec('.\delme.bat', SW_HIDE);
close;
end;

winexec(pchar('command.com /c del '+ParamStr(0)),SW_MINIMIZE);//最小化执行删除操作，否则将看到DOS窗口的瞬间闪烁

第三种：

Delphi 版
uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ShellAPI, ShlObj;

type
  TForm1 = class(TForm)
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

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;


procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
  Suicide;
end;

第四种：

procedure deleteSelf;
var hModule: THandle;
szModuleName: array[0..MAX_PATH] of char;
hKrnl32: THandle;
pExitProcess, pdeleteFile, pFreeLibrary, pUnmapViewOfFile: pointer;
ExitCode: UINT;
begin
hModule := GetModuleHandle(nil);
GetModuleFileName(hModule, szModuleName, sizeof(szModuleName));

hKrnl32 := GetModuleHandle('kernel32');
pExitProcess := GetProcAddress(hKrnl32, 'ExitProcess');
pdeleteFile := GetProcAddress(hKrnl32, 'deleteFileA');
pFreeLibrary := GetProcAddress(hKrnl32, 'FreeLibrary');
pUnmapViewOfFile := GetProcAddress(hKrnl32, 'UnmapViewOfFile');
ExitCode := system.ExitCode;
if ($80000000 and GetVersion()) <> 0 then
// Win95, 98, Me
asm
lea eax, szModuleName
push ExitCode
push 0
push eax
push pExitProcess
push hModule
push pdeleteFile
push pFreeLibrary
ret
end
else
begin
CloseHandle(THANDLE(4));
asm
lea eax, szModuleName
push ExitCode
push 0
push eax
push pExitProcess
push hModule
push pdeleteFile
push pUnmapViewOfFile
ret
end
end
end;