How to check country short form

Question

I am having these two table's

Country Table Details Table
Id CountryId CountryName Id CountryId Description
-------------------------------------- ----------------------------------
1 1 UK 1 1 xxxxx
2 2 USA 2 2 YYYYY

Design Page

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i will collect country name and description and save details to database

My Problem
if user give the country name as United Kingdom and give description and click save..
@the time i my database i will use it as UK But user enter as United Kingdom occurs mismatch
if User enter as full formed country_name how to i identify the short form of that particular country.

For example:if user enter United Kingdom convert to UK
How do i will check it..

i am looking on this => is there any online website to do this?
Please Say any Idea.
~Thanks.

Vulpes · Answer

Instead of allowing the user to enter the country name why don't you have a drop-down containing the names of all allowable countries from which the user can select one? In my experience that's what most sites do nowadays as you don't have to worry about abbreviations capitalization and mis-spellings.