[JS] select option 선택 값 출력

function change(){
	
	var values = document.getElementById('test').value;
	document.getElementById('show').value = values;
}

	<select id="test" onchange="change()">
		<option value="vip">vip</option>
		<option value="gold">gold</option>
		<option value="silver">silver</option>
	</select>
	<input type="text" id="show"><br>

❓ 선택 값에 따라 다른 select 값 변경

등급별로 할인율을 다르게 설정했습니다

function change(){
	
	var values = document.getElementById('test').value;
	document.getElementById('show').value = values;
    
    /* 등급 변경시 가격 옵션 초기화 */
	document.getElementById('show2').value = "";
	document.getElementById('test2').options[0].selected = true;
}

function change2(){
	var values3 = document.getElementById('test').value;
	var values2 = document.getElementById('test2').value;
	
	if(values3 == 'vip') values2 *= 0.5;
	if(values3 == 'gold') values2 *= 0.7;
	if(values3 == 'silver') values2 *= 0.9;
	
	document.getElementById('show2').value = values2;
}

	<select id="test" onchange="change()">
		<option value="vip">vip</option>
		<option value="gold">gold</option>
		<option value="silver">silver</option>
	</select>
	<input type="text" id="show">

	<select id="test2" onchange="change2()">
		<option value="10000">10000</option>
		<option value="20000">20000</option>
		<option value="30000">30000</option>
	</select>
	<input type="text" id="show2">