如何同时解决两个ajax请求的冲突

Question

I have one nominal.jsp page,which includes header.jsp.Here i am using Ajax for the first time, for the request in header.jsp,then for the second time Ajax request is called to the nominal.jsp,i am facing the conflict issue in the Ajax request. 我有一个nominal.jsp页面，其中包含header.jsp。在这里，我第一次使用Ajax，用于header.jsp中的请求，然后第二次将Ajax请求调用到名义.jsp，我正面临Ajax请求中的冲突问题。 Because of this issue,my preferred drop-down list is not displayed. 由于这个问题，我的首选下拉列表没有显示。 Sometimes when response is entered in the JavaScript, the drop-downs are displayed and if the response are not entered in the JavaScript, the drop-downs are not displayed. 有时，当在JavaScript中输入响应时，会显示下拉列表；如果未在JavaScript中输入响应，则不会显示下拉列表。 Tried my level best to resolve the issue, but could not resolve it. 尽我最大的努力解决了该问题，但无法解决。 Please help me guys 请帮我

thank u, 感谢你，

My header.jsp code: 我的header.jsp代码：

<script>
headerDisplay();
function headerDisplay()
{   var url ='<%=request.getContextPath()%>/summary?operation=header';
    transactionRequest(url);    
}  
function transactionRequest(url)
{
        if (window.XMLHttpRequest) 
         {              
            req = new XMLHttpRequest();                   
            req.onreadystatechange = transactionResponse;                   
                     try
                     { 
                               req.open("POST", url, true); //was get                   
                           }
                    catch(e) 
                     {
                        alert("Problem Communicating with Server\n"+e);
                     }                  
              req.send(null);
        }       

         else if (window.ActiveXObject) 
        { 
             // IE
            req = new ActiveXObject("Microsoft.XMLHTTP");
            if (req)
                { 

                    req.onreadystatechange = transactionResponse;  
                    req.open("POST", url, true);
                    req.send();
                }
        }  
}
function transactionResponse()
{         
      if (req.readyState == 4)  // Complete
       {
                 if (req.status == 200) // OK response

             {      var servletVal = req.responseText;      
                 var myObject = eval('(' + servletVal + ')');                      
                     var userId = myObject.userId;

}}}......

</script>


And,this is my nono.jsp code:


<%@include file="/pages/common/header.jsp"%>

<script>
function displayNominal()
{
    document.getElementById("ajaxLoading").style.display="block";
    var url ='<%=request.getContextPath()%>'+'/nominalList';
    postRequest(url);
}

function postRequest(url) {
        if (window.XMLHttpRequest) {
        req = new XMLHttpRequest();
        req.onreadystatechange = nominalSelect;
        try {
            req.open("POST", url, true); //was get                  
        } catch (e) {
            alert("Problem Communicating with Server\n" + e);
        }
        req.send(null);
    } else if (window.ActiveXObject) {
        // IE
        req = new ActiveXObject("Microsoft.XMLHTTP");
        if (req) {
            req.onreadystatechange = nominalSelect;
            req.open("POST", url, true);
            req.send();
        }
    }

}
function nominalSelect() {

    if (req.readyState == 4) // Complete
    {

        if (req.status == 200) // OK response
        {
            var servletVal = req.responseText;

            var myObject = eval('(' + servletVal + ')');
            var userId = myObject.userId;
            if (userId == null || userId == "") {
                window.location = '/accounts1/?status=session';
            }
}}..

</script>

<body class="bodystyle" onload="displayNominal()">
<% if("N".equals(roleDemoStatus))
                 {%>
<!-- /#demo Header -->
    <div style="top: 0px; display: block;" id="header" class="fixed">
        <div class="outer">
            <h1 class="blog-title" style="text-align:center;margin-top:10px;"><span style="font-weight: normal; color:#777777; font-size: 30px;">accounts<font color="#5DA915">1</font>.co</span> Demo Only - <a href="https://accounts1.co/accounts1/pages/userRegistration/signup1.jsp"><font color="red">Click Here</font></a> To Use For Free Forever</h1>
        </div><!-- .outer -->
        <div style="display: block;" class="shadow"></div>
    </div>
<!-- /#Demo Header -->
    <%}  %> 
</body>

Again thanks for advance. 再次感谢您的推进。

Answer 1

Use a single callback and a try/catch block to enforce the request order: 使用单个回调和try/catch块强制执行请求顺序：

function transactionResponse()
  {
  // Check whether this is the initial callback or a subsequent one
  if (!!transactionResponse.state)
    {        
      try
        {
        //POST data from the GET request
        }
      catch(e)
        {
        //Get data from the GET request
        }
      }

  // Set state after the initial callback reference
  else
    {
    transactionResponse.state = this;
    }        
  }

References 参考文献

Long Polling Experiment 长轮询实验

如何同时解决两个ajax请求的冲突

问题描述

1 个解决方案

解决方案1
0 2015-07-24 02:02:44

如何同时解决两个ajax请求的冲突

问题描述

1 个解决方案

解决方案1 0 2015-07-24 02:02:44

解决方案1
0 2015-07-24 02:02:44