在我的web应用程序我生成ID动态内容。下面我code

In my web app I generate dynamic content for id. Below my code

function lookup(){
<% List<UserOrganization> el = (List<UserOrganization>) request.getAttribute("uselist");%>
<% for (int i = 0; i < el.size(); i++) {%>   
        var email<%out.print(i);%>="<%out.print(el.get(i).getUser_1().getEmailId());%>";
        $.ajax({
            type: "POST",
            url: "EveConnectOutletsCount",
            data: {
                email:email<%out.print(i);%>
            },

            success: function(data) {

                $('#ec<%out.print(i);%>').html(data)

            }  
        });
<% }%>           
}

JSP页面：

<s:iterator value="uselist">  
      <span id="ec<%=n%>"></span>
</s:iterator>

本页面执行罚款，如果 uselist 有一定价值。它抛出500错误code。如果 uselist 是空的。 我怎样才能避免这个错误？

This page executes fine, if uselist has some value. It throws 500 error code if uselist is empty. How can I avoid this error?

推荐答案

我通过增加低于code解决了这个问题。

I solved the problem by adding below code.

function lookup() {
'<s:if test="uselist.size()>0">'
  <% List<UserOrganization> el = (List<UserOrganization>) request.getAttribute("uselist");%>
<% for (int i = 0; i < el.size(); i++) {%>    
    var email<%out.print(i);%>="<%out.print(el.get(i).getUser_1().getEmailId());%>";
    $.ajax({
        type: "POST",
        url: "EveConnectOutletsCount",
        data: {
            email:email<%out.print(i);%>
        },
        success: function(data) {
            $('#ec<%out.print(i);%>').html(data)
        }
    });
<% }%>
'</s:if>'
}

因此​​，如果列表空，我的code不会产生空指针异常。

so if list is null, my code wont generates null pointer exception.