How to extract SummaryInformation from msi file

We can use "WindowsInstaller.Installer" object to extract SummaryInformation from an MSI file.
Summary Information Stream Property Set
http://msdn.microsoft.com/en-us/library/aa372045(VS.85).aspx
Database.SummaryInformation Property
http://msdn.microsoft.com/en-us/library/aa368257(VS.85).aspx
Installer.SummaryInformation Property
http://msdn.microsoft.com/en-us/library/aa369486(VS.85).aspx