[JavaScript] SelectBox multiple

function setDisplayResult() {

if(!checkIpValues()) return;

var x = document.getElementById("ipSelectBox");

var option=document.createElement("option");

option.text= "kiwi"

try {

 // for IE earlier than version 8

 x.add(option,x.options[null]);

}catch (e) {

 x.add(option,null);

}

}

function removeOption() {

var obj = document.getElementById("ipSelectBox");

var length = obj.length;

if( length > 0 ) {

for( var i=0; i<length; i++ ) {

obj.remove(obj.selectedIndex);

}

}else {

alert("삭제 대상을 선택 해 주세요!");

}

}

<div id="selectDiv" style="position:absolute;left:370px;top:80px">

<select id="ipSelectBox" name="ipSelectBox" size="4" multiple="multiple" style="border-style:Groove;width:200px;height:200px"></select>

</div>

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