create sfx droplet.

using 7zip.bat

@SETLOCAL
@SET _7ZIP_HOME=C:\Program Files\7-Zip

@REM ----------------------------------------------------------------------------------------------
@REM param init
@REM ----------------------------------------------------------------------------------------------
@SET IN_FILE=%~1
@SET OUT_FILE=%~dpn1.exe

@REM ----------------------------------------------------------------------------------------------
@REM execute
@REM ----------------------------------------------------------------------------------------------
@pushd "%~dp0"
@copy /b "%_7ZIP_HOME%\7z.sfx" + "%IN_FILE%" "%OUT_FILE%"
@popd

@REM ----------------------------------------------------------------------------------------------
@REM wait
@REM ----------------------------------------------------------------------------------------------
@ping -n 3 localhost > nul
@ENDLOCAL

using winrar.bat

@SETLOCAL
@SET WINRAR_HOME=C:\Program Files\WinRAR
@REM @SET SFX=Default.SFX
@REM @SET SFX=Default64.SFX
@REM @SET SFX=WinCon.sfx
@REM @SET SFX=WinCon64.SFX
@REM @SET SFX=Zip.SFX
@REM @SET SFX=Zip64.SFX

@REM ----------------------------------------------------------------------------------------------
@REM param init
@REM ----------------------------------------------------------------------------------------------
@SET PATH=%WINRAR_HOME%;%PATH%
@SET IN_FILE=%~1
@SET OUT_FILE=%~dpn1.exe


@REM ----------------------------------------------------------------------------------------------
@REM execute
@REM ----------------------------------------------------------------------------------------------
@pushd "%~dp0"

@IF EXIST "%OUT_FILE%" (
  @DEL "%OUT_FILE%"
  @ECHO deleted output file.
  @ECHO   %OUT_FILE%
  @ECHO.
)

@IF /I "%SFX%" NEQ "" (
  @COPY /b /y "%WINRAR_HOME%\%SFX%" .\ > nul
  @ECHO copy sfx file.
  @ECHO   %SFX%
  @ECHO.
)

@WinRAR.exe s%SFX% "%IN_FILE%"
@IF NOT "%ERRORLEVEL%"  EQU "0" (
  @ECHO convert faild...
) ELSE (
  @ECHO converted.
  @ECHO   %OUT_FILE%
)
@ECHO.
@IF /I "%SFX%" NEQ "" (
  @del %SFX%"
  @ECHO delete sfx file.
  @ECHO.
)
@popd
@REM ----------------------------------------------------------------------------------------------
@REM eait
@REM ----------------------------------------------------------------------------------------------
@ping -n 3 localhost > nul
@ENDLOCAL