private string  GetProductCode()
        {
            System.Type oType = System.Type.GetTypeFromProgID("WindowsInstaller.Installer");
            Installer inst = System.Activator.CreateInstance(oType) as Installer;
            Database DB = inst.OpenDatabase("msi文件完整路径", MsiOpenDatabaseMode.msiOpenDatabaseModeReadOnly);
string str = "SELECT * FROM Property WHERE Property = 'ProductCode'";

            WindowsInstaller.View thisView = DB.OpenView(str);
            thisView.Execute();
            WindowsInstaller.Record thisRecord = thisView.Fetch();
string result = thisRecord.get_StringData(2);

return result;
        }