nsis 檢測vcredist_x86是否安裝

; 安裝VC環境
Function InstallVC
   Push $R0
   ClearErrors
   ReadRegDword $R0 HKLM "SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{FF66E9F6-83E7-3A3E-AF14-8DE9A809A6A4}" "Version" 

   ; 檢測含有vc的注冊表信息是否存在
   IfErrors 0 VSRedistInstalled
   Exec "$INSTDIR\vcredist_x86.exe /q"   ;若不存在，執行靜默安裝
   StrCpy $R0 "-1" 
   ; MessageBox MB_OK  $R0 

VSRedistInstalled:
   ; MessageBox MB_OK  "已安裝" 
   Exch $R0
 ; Delete "$INSTDIR\vcredist_x86." 
FunctionEnd

測試已通過，若檢測到未安裝vcredist_x86,執行靜默安裝。