让批处理也函数化

@ECHO OFF

SET V1=66
SET V2=999
SET V3=888
SET V4=99999
SET VSUM=0

CALL ::SUM V1 V2 VSUM
ECHO %V1% ^+ %V2% = %VSUM%

CALL ::SUM V3 V4 VSUM
ECHO %V3% ^+ %V4% = %VSUM%

CALL :ECHOFUNCION "Test string"

ECHO Done!
PAUSE > NUL

 
:SUM
SET /A %3=%1+%2
GOTO :EOF

:ECHOFUNCION
ECHO You put %1
GOTO :EOF