Finding logical drive attributes in C#

I need to find logical drive attributes for the system that my program installs on. I'm using the following code right now:

foreach (string s in Directory.GetLogicalDrives())
{
DirectoryInfo r = new DirectoryInfo(s);
if(-1 == r.Attributes.ToString().IndexOf("ReadOnly") && ...)
{
...
}

This gives me the drives and if they are read-only and system, but I need more. I need to know if the drive is removable and if the drive is a mapped drive. Can any one please help me.

Eric