How to get a list of all published methods for a given class

Problem/Question/Abstract:

Is there a way to get a list of all published methods for a given class? Preferably, I'd like to fill a TList with references to them, but even the text representation would work.

Answer:

Enumerate the published methods of a class and all its ancestor classes:

procedure EnumMethods(aClass: TClass; lines: TStrings);

type
  TMethodtableEntry = packed record
    len: Word;
    adr: Pointer;
    name: ShortString;
  end;
  {Note: name occupies only the size required, so it is not a true shortstring!
        The actual entry size is variable, so the method table is not an array
        of         TMethodTableEntry!}

var
  pp: ^Pointer;
  pMethodTable: Pointer;
  pMethodEntry: ^TMethodTableEntry;
  i, numEntries: Word;
begin
  if aClass = nil then
    Exit;
  pp := Pointer(Integer(aClass) + vmtMethodtable);
  pMethodTable := pp^;
  lines.Add(format('Class %s: method table at %p', [aClass.Classname, pMethodTable]));
  if pMethodtable <> nil then
  begin
    {first word of the method table contains the number of entries}
    numEntries := PWord(pMethodTable)^;
    lines.Add(format('  %d published methods', [numEntries]));
    {make pointer to first method entry, it starts at the second word of the table}
    pMethodEntry := Pointer(Integer(pMethodTable) + 2);
    for i := 1 to numEntries do
    begin
      with pMethodEntry^ do
        lines.Add(format('  %d: len: %d, adr: %p, name: %s', [i, len, adr, name]));
      {make pointer to next method entry}
      pMethodEntry := Pointer(Integer(pMethodEntry) + pMethodEntry^.len);
    end;
  end;
  EnumMethods(aClass.ClassParent, lines);
end;

procedure TForm2.Button1Click(Sender: TObject);
begin
  memo1.clear;
  EnumMethods(Classtype, memo1.lines);
end;