NSIS：判断D盘存在与否确定安装路径

!include "MUI2.nsh"
!include "FileFunc.nsh"

RequestExecutionLevel admin

Name "判断D盘存在与否确定安装路径"
Caption "判断D盘存在与否确定安装路径"
OutFile "test.exe"
InstallDir "$PROGRAMFILES\flighty app"
;读取注册中的安装路径，如果不存在则按照默认路径。
InstallDirRegKey HKCU "Software\flighty app" ""
BrandingText "www.flighty.cn"

!insertmacro MUI_PAGE_DIRECTORY
!insertmacro MUI_PAGE_INSTFILES
!insertmacro MUI_LANGUAGE "SimpChinese"

Section
SectionEnd

Section -Post
  ;在注册表中写入安装路径
  WriteRegStr HKCU "Software\flighty app" "" $INSTDIR
SectionEnd


Function .onInit
  ReadRegStr $R4 HKCU "Software\flighty app" ""
	 StrCmp $R4 "" NO YES
	 NO:
	 StrCpy $R1 "D:\"
	 ${DriveSpace} $R1 "/D=F /S=M" $R0
	 ${If} $R0 = null
	 	 StrCpy $R1 "$PROGRAMFILES\flighty app"
	 ${Else}
	 	 StrCpy $R2 "Program Files"
	 	 StrCpy $R3 "flighty app"
	 	 StrCpy $R1 "D:\$R2\$R3"
	 ${EndIf}
	 ;重新设置$INSTDIR默认值
	 StrCpy $INSTDIR "$R1"
	 YES:
	 Goto +1
FunctionEnd