TIdEMailAddressItem = class(TIdCollectionItem);

The TIdEMailAddressItem is a TIdCollectionItem descendant that structures components in an EMail address into an RFC 2822-compliant form. 

TIdEMailAddressItem can also be used to parse the Text representing an RFC 2822-compliant EMail address into the component values defined in RFC 2822. These values are stored in properties, including: 

TIdEMailAddressItem also provides encoding and decoding of quoted characters as specified in the the lexical requirements for character quoting in RFC 2822. 

TIdEMailAddressItem is the collection item class used in the TIdEMailAddressList collection, and for properties representing a single email address in TIdMessage.