is the electron gain enthalpy and electron affinity the same or different????

Electron gain enthalpy is the tendency of an gaseous atom to form anion.It is defined as the enthaply change taking place when an isolated gaseous atom accepts an e- to form monovalent gaseous anion.It may be expressed as--
A(g) + e^-- ----------------> A^-(g) deltaH = delta_egH
Now this process of adding an e- can either be exothermic or endothermic which depends on element.Large -ive value of e- gain enthalpy reflects the greater tendency of an atom to accept the e-.For ex- halogens have very high -ive gain enthalpies because by gaining just 1e- they can attain noble gas configuration but noble gases have large positive gain enthalpies because the additional e- goes to the next principal shell resulting in a very unstable electronic configuration.
Energy changes in the above process can also be represent in terms of electron affinity,which is generally taken to be equal to the --ive of the e- gain enthalpy.
1).If the energy is released on adding an e- to the gaseous atom,then e- affinity is taken as positive.
2).If the energy has to be supplied when an e- is added then e- affinity is taken as negative.