Check for .NET4.5+ with NSIS

Question

All, I am aware of the following methods to check the framework version in NSIS. For .NET4.0+ I currently use

Function IsDotNetInstalled

    StrCpy $0 \"0\         


        

Answer 1

In the end I went with the following function which utilises the answer above. This method first creates a directory "$INSTDIR\dotNETFramework" which contains the .NET web installer:

Function CheckAndInstallDotNet
    ; Installer dotNetFx45_Full_setup.exe avalible from http://msdn.microsoft.com/en-us/library/5a4x27ek.aspx
    ; Magic numbers from http://msdn.microsoft.com/en-us/library/ee942965.aspx
    ClearErrors
    ReadRegDWORD $0 HKLM "SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full" "Release"
    IfErrors NotDetected
    ${If} $0 >= 378389
        DetailPrint "Microsoft .NET Framework 4.5 is installed ($0)"
    ${Else}
    NotDetected:
        MessageBox MB_YESNO|MB_ICONQUESTION ".NET Framework 4.5+ is required for ProgramX2013, \
            do you want to launch the web installer? This requires a valid internet connection." IDYES InstallDotNet IDNO Cancel 
        Cancel:
            MessageBox MB_ICONEXCLAMATION "To install ProgramX, Microsoft's .NET Framework v${DOT_MAJOR}.${DOT_MINOR} \
                (or higher) must be installed. Cannot proceed with the installation!"
            ${OpenURL} "${WWW_MS_DOTNET4_5}"
            RMDir /r "$INSTDIR" 
            SetOutPath "$PROGRAMFILES"
            RMDir "$INSTDIR" 
            Abort

        ; Install .NET4.5.
        InstallDotNet:
            DetailPrint "Installing Microsoft .NET Framework 4.5"
            SetDetailsPrint listonly
            ExecWait '"$INSTDIR\dotNETFramework\dotNetFx45_Full_setup.exe" /passive /norestart' $0
            ${If} $0 == 3010 
            ${OrIf} $0 == 1641
                DetailPrint "Microsoft .NET Framework 4.5 installer requested reboot."
                SetRebootFlag true 
            ${EndIf}
            SetDetailsPrint lastused
            DetailPrint "Microsoft .NET Framework 4.5 installer returned $0"
    ${EndIf}

    ; Now remove the dotNETFramework directory and contents.
    RMDir /r "$INSTDIR\dotNETFramework" 
FunctionEnd

This method seemlessley launches the .NET4.5 installer if there is an internet connection and returns after the installation is complete.

I hope this helps someone else.