首先需要的js及css，我是直接在官網上下載下傳的
廢話不多說，直接上代碼
<!DOCTYPE html>
<html>
<head>
<title>layui下拉框多選</title>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta name="renderer" content="webkit">
<meta http-equiv="X-UA-Compatible" content="IE=9; IE=8; IE=7; IE=EDGE">
<link rel="stylesheet" href="layui/layui.css" target="_blank" rel="external nofollow" >
<script src="layui/layui.js" charset="utf-8"></script>
<link rel="stylesheet" href="layui/formSelects-v4.css" target="_blank" rel="external nofollow" >
</head>
<body>
<div style="padding: 20px; height: 600px;">
<form class="layui-form" action="">
<div style="width: 300px; display: inline-block; margin-right: 10px;">
<select name="city" xm-select="method-value-example1">
<option value="1" >北京</option>
<option value="2" >上海</option>
<option value="3">廣州</option>
<option value="4" >深圳</option>
<option value="5">天津</option>
</select>
</div>
</form>
<button class="layui-btn"
onclick="on()">擷取已選中資料的字元串值</button>
</div>
</body>
<script src="layui/layui.all.js" type="text/javascript" charset="utf-8"></script>
<script src="layui/formSelects-v4.js" type="text/javascript" charset="utf-8"></script>
<script type="text/javascript">
var formSelects = layui.formSelects;
</script>
<script>
formSelects.value('method-value-example1', ['2','4']);//指派選中，為option的value值，數組形式，給上海和深圳選中
</script>
<script>
function on(){
var a=JSON.stringify(formSelects.value('method-value-example1', 'valStr'));//值為2,4（選中為上海，深圳）
alert(a);
}
</script>
</html>
不懂的方法可以看文檔，裡面都解釋的很清楚，js和css裡面都有下載下傳位址
點選進入
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