GeoNames API for Drupal - the whole world in one function

This code compiles a dropdown list of all countries which you may use in forms. The first time it may take a second or two to compile the list, but after that the box will compile spontaneously from the cache.

1. Install the 'GeoNames API' and 'countryinfo' modules on your site.
2. Create a new page on your site, and set Input format to PHP code.
3. Add the following code to the page:

<?php
$result = geonames_query('countryinfo');
foreach ($result->results as $country) {
  $optionlist .= sprintf('<option value="%s">%s</option>', $country['countrycode'], $country['countryname']);
}
?>

<form>
  <select><? print $optionlist ?></select>
</form>


Example Result: AndorraAfghanistanAntigua and BarbudaAnguillaAlbaniaArmeniaNetherlands AntillesAngolaAntarcticaArgentinaAmerican SamoaAustriaAustraliaArubaAzerbaijanBosnia and HerzegovinaBarbadosBangladeshBelgiumBurkina FasoBulgariaBahrainBurundiBeninBermudaBruneiBoliviaBrazilBahamasBhutanBotswanaBelarusBelizeCanadaCocos IslandsCongo - KinshasaCentral African RepublicCongo - BrazzavilleSwitzerlandIvory CoastCook IslandsChileCameroonChinaColombiaCosta RicaCubaCape VerdeChristmas IslandCyprusCzech RepublicGermanyDjiboutiDenmarkDominicaDominican RepublicAlgeriaEcuadorEstoniaEgyptWestern SaharaEritreaSpainEthiopiaFinlandFijiFalkland IslandsMicronesiaFaroe IslandsFranceGabonUnited KingdomGrenadaGeorgiaFrench GuianaGuernseyGhanaGibraltarGreenlandGambiaGuineaGuadeloupeEquatorial GuineaGreeceSouth Georgia and the South Sandwich IslandsGuatemalaGuamGuinea-BissauGuyanaHondurasCroatiaHaitiHungaryIndonesiaIrelandIsraelIsle of ManIndiaBritish Indian Ocean TerritoryIraqIranIcelandItalyJerseyJamaicaJordanJapanKenyaKyrgyzstanCambodiaKiribatiComorosSaint Kitts and NevisNorth KoreaSouth KoreaKuwaitCayman IslandsKazakhstanLaosLebanonSaint LuciaLiechtensteinSri LankaLiberiaLesothoLithuaniaLuxembourgLatviaLibyaMoroccoMonacoMoldovaMadagascarMarshall IslandsMacedoniaMaliMyanmarMongoliaMacaoNorthern Mariana IslandsMartiniqueMauritaniaMontserratMaltaMauritiusMaldivesMalawiMexicoMalaysiaMozambiqueNamibiaNew CaledoniaNigerNorfolk IslandNigeriaNicaraguaNetherlandsNorwayNepalNauruNiueNew ZealandOmanPanamaPeruFrench PolynesiaPapua New GuineaPhilippinesPakistanPolandSaint Pierre and MiquelonPitcairnPuerto RicoPalestinian TerritoryPortugalPalauParaguayQatarReunionRomaniaRussiaRwandaSaudi ArabiaSolomon IslandsSeychellesSudanSwedenSingaporeSaint HelenaSloveniaSvalbard and Jan MayenSlovakiaSierra LeoneSan MarinoSenegalSomaliaSurinameSao Tome and PrincipeEl SalvadorSyriaSwazilandTurks and Caicos IslandsChadFrench Southern TerritoriesTogoThailandTajikistanTokelauTurkmenistanTunisiaTongaTurkeyTrinidad and TobagoTuvaluTaiwanTanzaniaUkraineUgandaUnited StatesUruguayUzbekistanSaint Vincent and the GrenadinesVenezuelaBritish Virgin IslandsU.S. Virgin IslandsVietnamVanuatuWallis and FutunaSamoaYemenMayotteSouth AfricaZambiaZimbabwe

Note that the list is ordered by Country Code (we display only the Country Name, but the Country Code is used as value). To learn how to order the results, read the Ordered Country Dropdown code example.

Explanation:
The geonames_query function uses the 'countryinfo' module to find the results. If no parameters are passed, all countries are returned. We loop through the results with foreach and generate some option HTML for a dropdown list (select list).
Then we display a form, and put the option list between two select tags, just to display our result.

Note: The first time you run the query, the server may use some time (some seconds) for the request. However, if you have the cache enabled - the country data will be retrieved from the cache on the next request (which is lightning fast!).