///<Summary>returns True if the beginning of A matches B exactly for B's entire length</Summary>
public static bool StartsWith(cPidl A, cPidl B)
{
return A.StartsWith(B);
}
///<Summary> Compares a candidate Ancestor PIDL with a Child PIDL and
/// returns True if Ancestor is an ancestor of the child.
/// if fParent is True, then only return True if Ancestor is the immediate
/// parent of the Child</Summary>
public static bool IsAncestorOf(IntPtr AncestorPidl, IntPtr ChildPidl, bool fParent)
{
bool returnValue;
if (ShellDll.Is2KOrAbove())
{
return ExpTreeLib.ShellDll.ILIsParent(AncestorPidl, ChildPidl, fParent);
}
else
{
cPidl Child = new cPidl(ChildPidl);
cPidl Ancestor = new cPidl(AncestorPidl);
returnValue = Child.StartsWith(Ancestor);
if (! returnValue)
{
return returnValue;
}
if (fParent) // check for immediate ancestor, if desired
{
object[] oAncBytes = Ancestor.Decompose();
object[] oChildBytes = Child.Decompose();
if (oAncBytes.Length != (oChildBytes.Length - 1))
{
returnValue = false;
}
}
}
return returnValue;
}