dedeCMS 织梦ajax跨域提交自定义表单和验证码问题

<script type="text/javascript" src="http://apps.bdimg.com/libs/jquery/1.6.4/jquery.min.js"></script> <script> function send() {     $.ajax({         cache: true,         type: "POST",         url: "http://B站域名/plus/diy.php",         data: $('#diyform').serialize(),         xhrFields: { withCredentials: true },         crossDomain: true,         success: function(data) {             if (data == "success") {                 alert('发送成功!');             } else {                 alert('发送失败!');             }         }     }); } </script> <form action="" enctype="multipart/form-data" method="post" id="diyform">     <input type="hidden" name="action" value="post" />     <input type="hidden" name="diyid" value="2" />     <input type="hidden" name="do" value="2" />     <input type="hidden" name="dede_fields" value="name,text" />     <input type="hidden" name="dede_fieldshash" value="c2be5bb5ec45d9d01ca9f60dc469b3fb" />     <p>姓名：<input type='text' name='name' id='name' /></p>     <p>验证码：<input type="text" name="validate"><img src="http://B站域名/include/vdimgck.php" align="absmiddle" onclick="this.src='http://B站域名/include/vdimgck.php?tag=' + Math.random();" style="cursor:pointer;"></p>     <div onclick="send()">提交</div> </form>