Internet Direct (Indy) Version 9.0.1 Beta
TIdHeaderList.Names
Access header names by position.

property Names [Index: Integer]: string;
Description
Names is a read-only String property that provides indexed access to header names for the header list. Names works like Borland's TStrings.Names except that it uses the delimiter in NameValueSeparator and respects the case sensitivity flag in CaseSensitive.