///<Summary>Returns true if the CPidl input parameter exactly matches the
/// beginning of this instance of CPidl</Summary>
public bool StartsWith(cPidl cp)
{
byte[] b = cp.PidlBytes;
if (b.Length > m_bytes.Length)
{
return false; //input is longer
}
int i;
for (i = 0; i <= b.Length - 3; i++) //allow for nulnul at end of cp.PidlBytes
{
if (b[i] != m_bytes[i])
{
return false;
}
}
return true;
}
///<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>Returns True if input cPidl's content exactly match the
/// contents of this instance</Summary>
public bool IsEqual(cPidl other)
{
bool returnValue;
returnValue = false; //assume not
if (other.Length != this.Length)
{
return returnValue;
}
byte[] ob = other.PidlBytes;
int i;
for (i = 0; i <= this.Length - 1; i++) //note: we look at nulnul also
{
if (ob[i] != m_bytes[i])
{
return returnValue;
}
}
return true; //all equal on fall thru
}
///<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;
}
