PS > Get-Member -InputObject $anObjectInstance
This will return all members of the type instance. Here is a part of a sample output for String instance
TypeName: System.String
Name MemberType Definition
---- ---------- ----------
Clone Method System.Object Clone(), System.Object ICloneable.Clone()
CompareTo Method int CompareTo(System.Object value), int CompareTo(string strB), i...
Contains Method bool Contains(string value)
CopyTo Method void CopyTo(int sourceIndex, char[] destination, int destinationI...
EndsWith Method bool EndsWith(string value), bool EndsWith(string value, System.S...
Equals Method bool Equals(System.Object obj), bool Equals(string value), bool E...
GetEnumerator Method System.CharEnumerator GetEnumerator(), System.Collections.Generic...
GetHashCode Method int GetHashCode()
GetType Method type GetType()
...