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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              <select name="prefecture">
	<option value="都道府県を選択してください…">都道府県を選択してください…</option>
	<option value="東京都">東京都</option>
	<option value="新潟県">新潟県</option>
</select>

<select name="city">
	<option value="市町村を選択してください…">市町村を選択してください…</option>
	<option value="千代田区" data-prefecture="東京都">千代田区</option>
	<option value="中央区" data-prefecture="東京都">中央区</option>
	<option value="港区" data-prefecture="東京都">港区</option>
	<option value="新宿区" data-prefecture="東京都">新宿区</option>
	<option value="新潟市" data-prefecture="新潟県">新潟市</option>
	<option value="長岡市" data-prefecture="新潟県">長岡市</option>
	<option value="上越市" data-prefecture="新潟県">上越市</option>
</select>
            
          
!
            
              jQuery(document).ready(function($){
	var $pref = $('select[name="prefecture"]');
	var $city = $('select[name="city"]');
	var $cityOpts = $city.children('option');
	var cityFirstText = $cityOpts.first().text();

	$city.children('option:not(:first-child)').hide();

	$pref.on('change', function() {
		var prefName = $(this).val();
		var prefIndex = $pref.prop('selectedIndex');

		$cityOpts.show();

		if(prefIndex !== 0) {
			$cityOpts.each(function() {
				var eachPrefName = $(this).attr('data-prefecture');
				var cityName = $(this).val();
				if(eachPrefName !== prefName && cityName !== cityFirstText) {
					$(this).hide();
				}
			});
		} else {
			$cityOpts.hide();
		}
		$city.val(cityFirstText);
	});
});
            
          
!
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