按钮赋值传值到模态框表单的问题

想要点击修改按钮赋值给修改按钮,然后打开模态框传给表单,为什么我怎么传都传不进去,我是哪里步骤出问题了呢?

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
    <meta charset="utf-8"/>
    <title>会员信息维护-首页title>
    <style type="text/css">
        .myposition {
            position: relative;
            left: 280px;  }
    style>
    <script type="text/javascript" src="/vip/jquery/jquery-3.3.1.min.js">script>
    <link type="text/css" rel="stylesheet" href="/vip/bootstrap/css/bootstrap.min.css"/>
    <script type="text/javascript" src="/vip/bootstrap/js/bootstrap.min.js">script>
head>
<body>



<script>
    $('#updateModal').on('show.bs.modal', function(event) {
       ** modal.find('#ex1').val(name)**
    })
script>



<div class="modal fade" id="updateModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel">
    <div class="modal-dialog" role="document">
        <div class="modal-content">


            <div class="modal-body">
                <form class="form-inline">
                    <div class="form-group">
                        <label class="sr-only" >表单1label>
                        <input type="text" class="form-control" **id="ex1"** value="" placeholder="表单1">
                    div>
                form>
            div>

<form method="post" action="<%=request.getContextPath()%>/dormitoryAdmin?method=search">



<div class="myposition" style="top: 60px;">
    <table class="table table-condensed">
        <tr>
            <th>修改按钮th>
 
        tr>

        <c:forEach items="${list}" var="dormitoryAdmin" varStatus="vs">
            <tr>
       
                <td>
                    <div class="hidden-sm hidden-xs btn-group">
                        <a class="btn btn-sm btn-info"  data-toggle="modal" data-target="#updateModal"

                           **data-name="${dormitoryAdmin.SFZ}"**


                        >
                            <i class="glyphicon glyphicon-pencil">i>
                        a>
  div>
 td>
            tr>
        c:forEach>


    table>

div>

body>
html>





$('#updateModal').on('show.bs.modal', function(event) {
   // 加个延时试试，可能dom还没生成，找不到
    setTimeout(function (){
          modal.find('#ex1').val(name)
    }, 300)
})