'result = Environ( varname )
'实测，WIN7 下，XP只有29个，注意：不能用数字取，因为系统不同，内容不同
'1  ALLUSERSPROFILE=C:\ProgramData
'2  APPDATA=C:\Users\Administrator\AppData\Roaming
'3  CommonProgramFiles=C:\Program Files (x86)\Common Files
'4  CommonProgramFiles(x86)=C:\Program Files (x86)\Common Files
'5  CommonProgramW6432=C:\Program Files\Common Files
'6  COMPUTERNAME=YONGFANG
'7  ComSpec=C:\Windows\system32\cmd.exe
'8  DEVMGR_SHOW_DETAILS=1
'9  FP_NO_HOST_CHECK=NO
'10  HOMEDRIVE=C:
'11  HOMEPATH=\Users\Administrator
'12  LOCALAPPDATA=C:\Users\Administrator\AppData\Local
'13  LOGONSERVER=\\YONGFANG
'14  NUMBER_OF_PROCESSORS=8
'15  OS=Windows_NT
'16  Path=C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\
'17  PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC
'18  PROCESSOR_ARCHITECTURE=x86
'19  PROCESSOR_ARCHITEW6432=AMD64
'20  PROCESSOR_IDENTIFIER=Intel64 Family 6 Model 42 Stepping 7, GenuineIntel
'21  PROCESSOR_LEVEL=6
'22  PROCESSOR_REVISION=2a07
'23  ProgramData=C:\ProgramData
'24  ProgramFiles=C:\Program Files (x86)
'25  ProgramFiles(x86)=C:\Program Files (x86)
'26  ProgramW6432=C:\Program Files
'27  PSModulePath=C:\Windows\system32\WindowsPowerShell\v1.0\Modules\
'28  PUBLIC=C:\Users\Public
'29  SESSIONNAME=Console
'30  SystemDrive=C:
'31  SystemRoot=C:\Windows
'32  TEMP=S:\
'33  TMP=S:\
'34  USERDOMAIN=YONGFANG
'35  USERNAME=Administrator
'36  USERPROFILE=C:\Users\Administrator
'37  windir=C:\Windows
'38  windows_tracing_flags=3
'39  windows_tracing_logfile=C:\BVTBin\Tests\installpackage\csilogfile.log
'XP系统下------------------------------------------------------------------
'1  ALLUSERSPROFILE=C:\Documents and Settings\All Users
'2  APPDATA=C:\Documents and Settings\Administrator\Application Data
'3  CLIENTNAME=Console
'4  CommonProgramFiles=C:\Program Files\Common Files
'5  COMPUTERNAME=PC-20141206HRKK
'6  ComSpec=C:\WINDOWS\system32\cmd.exe
'7  FP_NO_HOST_CHECK=NO
'8  HOMEDRIVE=C:
'9  HOMEPATH=\Documents and Settings\Administrator
'10  LOGONSERVER=\\PC-20141206HRKK
'11  NUMBER_OF_PROCESSORS=2
'12  OS=Windows_NT
'13  Path=C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem
'14  PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH
'15  PROCESSOR_ARCHITECTURE=x86
'16  PROCESSOR_IDENTIFIER=x86 Family 6 Model 42 Stepping 7, GenuineIntel
'17  PROCESSOR_LEVEL=6
'18  PROCESSOR_REVISION=2a07
'19  ProgramFiles=C:\Program Files
'20  SESSIONNAME=Console
'21  SystemDrive=C:
'22  SystemRoot=C:\WINDOWS
'23  TEMP=C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp
'24  TMP=C:\DOCUME~1\ADMINI~1\LOCALS~1\Temp
'25  USERDOMAIN=PC-20141206HRKK
'26  USERNAME=Administrator
'27  USERPROFILE=C:\Documents and Settings\Administrator
'28  windir=C:\WINDOWS
'29  _DFX_INSTALL_UNSIGNED_DRIVER=1
'WIN10系统下  ------------------------------------------------------------
'1  ALLUSERSPROFILE=C:\ProgramData
'2  APPDATA=C:\Users\w10\AppData\Roaming
'3  CommonProgramFiles=C:\Program Files\Common Files
'4  COMPUTERNAME=WIN-5VHV9G20U4C
'5  ComSpec=C:\Windows\system32\cmd.exe
'6  FPS_BROWSER_APP_PROFILE_STRING=Internet Explorer
'7  FPS_BROWSER_USER_PROFILE_STRING=Default
'8  HOMEDRIVE=C:
'9  HOMEPATH=\Users\w10
'10  LOCALAPPDATA=C:\Users\w10\AppData\Local
'11  LOGONSERVER=\\WIN-5VHV9G20U4C
'12  NUMBER_OF_PROCESSORS=2
'13  OS=Windows_NT
'14  Path=C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\
'15  PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC
'16  PROCESSOR_ARCHITECTURE=x86
'17  PROCESSOR_IDENTIFIER=x86 Family 6 Model 42 Stepping 7, GenuineIntel
'18  PROCESSOR_LEVEL=6
'19  PROCESSOR_REVISION=2a07
'20  ProgramData=C:\ProgramData
'21  ProgramFiles=C:\Program Files
'22  PSModulePath=C:\Windows\system32\WindowsPowerShell\v1.0\Modules\
'23  PUBLIC=C:\Users\Public
'24  SESSIONNAME=Console
'25  SystemDrive=C:
'26  SystemRoot=C:\Windows
'27  TEMP=C:\Users\w10\AppData\Local\Temp
'28  TMP=C:\Users\w10\AppData\Local\Temp
'29  USERDOMAIN=WIN-5VHV9G20U4C
'30  USERDOMAIN_ROAMINGPROFILE=WIN-5VHV9G20U4C
'31  USERNAME=w10
'32  USERPROFILE=C:\Users\w10
'33  windir=C:\Windows
'34  __COMPAT_LAYER=DetectorsWin8
