How to get switch info (public or private network) using SOAP API ?

I can't find a way to get any information about VirtualSwitch using WS API. Only create and remove method:

* addVirtualSwitch

* removeVirtualSwitch

Also there is no common way to get info from  folder, like for PortGroups :

getMOREFs.inFolderByType(rootRef, "Network");

when I try

getMOREFs.inFolderByType(rootRef, "HostVirtualSwitch");

I've got exception: wrong type.

So my original goal is implement two list methods:

listPrivateNetrowrks() // portgroups or virtual switch with out public access (pnic associated)

listPublicNetrowrks()  // networks with public access realized with associated  pnic port to virtual switch

Please HELP!

vmware API makes me crazy ;(