select多选 multiple的使用

select多选  multiple的使用

<html>
<head>
<script type="text/javascript">
function showDiv(id){

	document.getElementById("selectOption").style.display="block";
	document.getElementById("selectOption").style.position="absolute";
	document.getElementById("selectOption").style.top=document.getElementById(id).offsetTop+25;
	document.getElementById("selectOption").style.left=document.getElementById(id).offsetLeft+20;
}
function selectM()
  {
var obj = document.getElementById("mySelect"); 
  alert(obj.selectedIndex);

  }
function checkselect(objname){
o = document.getElementById(objname);
t = document.getElementById("output");
var intvalue="";
for(i=0;i<o.length;i++){   
   if(o.options[i].selected){
    intvalue+=o.options[i].value+",";
   }
}
t.value=intvalue.substr(0,intvalue.length-1);
alert(intvalue);

}

</script>
</head>
<body>

<form>
<div id="selectOption" style='width:100px;height:50px;z-index:100;border:1px solid #0099FF;background:#cccccc;display:none;'>
	<select id="mySelect" multiple="multiple" size="4">
	  <option value='苹果'>苹果</option>
	  <option value='桃子'>桃子</option>
	  <option value='香蕉'>香蕉</option>
	  <option value='桔子'>桔子</option>
	</select>
	<input type="button" onclick="checkselect('mySelect')" value="checkselect">
</div>
选中的项目:<input type="text" name="output">
<input id="lalla" type="button" onclick="showDiv(this.id)" value="选择">
<br/>


</form>
<p>在您点击 “选择多个” 按钮之前,请尝试同一时候选取多个选项。在点击 “选择多个” 按钮之后,请再试一次。</p>

</form>
</body>
</html>


posted @ 2018-02-06 19:17  llguanli  阅读(680)  评论(0编辑  收藏  举报