JavaScript 异步回调函数实战：解决异步请求与业务逻辑执行顺序问题

function add(url,data) {
 var isExited = isExited(data); 
 if(!isExited){
  addRequest(url, data); 
 }
}

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<head>
 <meta charset="utf-8">
 <meta http-equiv="X-UA-Compatible" content="IE=edge">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>JS回调函数案例</title>
 <!-- Bootstrap -->
 <link href="<c:url value='/lib/bootstrap/css/bootstrap.min.css'/>" rel="stylesheet">

 <script type="text/javascript">

  /**
   * 删除的请求
   */
  function supplierDelete(element) {
   var id = element.parentNode.parentNode.cells[0].innerHTML;
   modalDeleteRequest('${pageContext.request.contextPath}/oms/supplier/remove/', id);
  }
 </script>
</head>
<body>
<!-- 顶部导航 -->
<div class="navbar navbar-inverse navbar-fixed-top" role="navigation" id="menu-nav">

</div>

<div class="container partner-table-container textFont">
 <table class="table table-striped detailTableSet">
  <caption><h2>JS回调函数案例</h2></caption>
  <br>
  <tr class="table-hover form-horizontal">
   <td class="info">123</td>
   <td class="info">123</td>
   <td class="info">123</td>
   <td class="info">123</td>
   <td class="info">123</td>
  </tr>
   <tr>
    <td>123</td>
    <td>123</td>
    <td>123</td>
    <td>123</td>
    <td>123</td>
    <td>
     <a onclick="supplierUpdate(this)">修改</a>&nbsp;
     <a onclick="supplierDelete(this)">删除</a>
    </td>
   </tr>
 </table>
</div>

<!--显示成功失败的modal-->
<%@include file="/modal-custom.jsp" %>

<script src="<c:url value='/lib/jquery-1.8.3.min.js'/>"></script>
<script src="<c:url value='/lib/bootstrap/js/bootstrap.min.js'/>"></script>
<script type="text/javascript" src="<c:url value='/js/modal-operate.js'/>"></script>
</body>
</html>

<script type="text/javascript">

  /**
   * 删除的请求
   */
  function supplierDelete(element) {
   var id = element.parentNode.parentNode.cells[0].innerHTML;
   modalDeleteRequest('${pageContext.request.contextPath}/oms/supplier/remove/', id);
  }
 </script>

<%@ page language="java" pageEncoding="UTF-8" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!-- 模态框（Modal） -->
<div class="modal fade" id="modal-result" tabindex="-1" role="dialog"
  aria-labelledby="myModalLabel" aria-hidden="true">
 <div class="modal-dialog">
  <div class="modal-content">
   <div class="modal-header">
    <button type="button" class="close"
      data-dismiss="modal" aria-hidden="true">
     &times;
    </button>
    <h4 class="modal-title" id="myModalLabel">
     信息
    </h4>
   </div>
   <div class="modal-body" id="modal-add-result-text">
   </div>
   <div class="modal-footer">
    <button type="button" class="btn btn-default"
      data-dismiss="modal">关闭
    </button>
   </div>
  </div>
  <!-- /.modal-content -->
 </div>
 <!-- /.modal -->
</div>

/**
 * 删除请求的操作
 * @param url 删除请求的url
 * @param id 删除的id
 */
function modalDeleteRequest(url, id) {
 confirmIsDelete(url, id, deleteRequest);
}
/**
 * 在删除警告框确认之后调用的回调函数
 * @param url
 * @param id
 */
function deleteRequest(url, id) {
 $.get(url + id, function (result) {
  $("#modal-add-result-text").text(result.msg);
  $("#modal-result").modal('show');
 }, "json");
}

/**
 * 弹出对话框确认是否删除
 * @param url 删除请求的url
 * @param id 删除请求的id
 * @param callback 回调函数，在最后的时候需要进行回调的函数
 */
function confirmIsDelete(url, id, callback) {
 var confirmDeleteDialog = $('<div class="modal fade"><div class="modal-dialog">'
  + '<div class="modal-content"><div class="modal-header"><button type="button" class="close" '
  + 'data-dismiss="modal" aria-hidden="true">&times;</button>'
  + '<h4 class="modal-title">确认删除</h4></div><div class="modal-body">'
  + '<div class="alert alert-warning">确认要删除吗？删除之后无法恢复哦！</div></div><div class="modal-footer">'
  + '<button type="button" class="btn btn-default" data-dismiss="modal">取消</button>'
  + '<button type="button" class="btn btn-success" id="deleteOK">删除</button></div></div>'
  + '</div></div>');

 confirmDeleteDialog.modal({
  keyboard: false
 }).on({
  'hidden.bs.modal': function () {
   $(this).remove();
  }
 });

 var deleteConfirm = confirmDeleteDialog.find('#deleteOK');
 deleteConfirm.on('click', function () {
  confirmDeleteDialog.modal('hide'); //隐藏dialog
  //需要回调的函数
  callback(deleteRequest(url, id));
 });
}

/**
 * 回调函数测试方法
 * 
 * @param callback
 * 回调的方法
 */
function testCallback(callback) {
 alert('come in!');
 callback();
}

/**
 * 被回调的函数
 */
function a() {
 alert('a');
}

/**
 * 开始测试方法
 */
function start() {
 testCallback(a);
}