ashx始终返回false，求解

alert的不是add，一直是false。       $(function () {
            $('#add').form(
            {
                url: '/Budget.ashx?action=add',
                success: function (data) {
                    alert(data);
}
            });
        });<body>
    <form id="add" method="post">
    <table>
        <tr>
            <td>
                项目种类：
            </td>
            <td>
                <select id="type" name="type" style="width: 200px;">
                    <option value="合同费用">合同费用</option>
                    <option value="运营保障费用">运营保障费用</option>
                </select>
            </td>
        </tr>
        <tr>
            <td>
                项目名称：
            </td>
            <td>
                <input id="title" name="title" type="text" style="width: 400px" />
            </td>
        </tr>
        <tr>
            <td>
                项目描述：
            </td>
            <td>
                <textarea id="describe" name="describe" style="width: 400px; height: 50px;"></textarea>
            </td>
        </tr>
        <tr>
            <td>
                核算码：
            </td>
            <td>
                <input id="acode" name="acode" type="text" style="width: 50px" />
                <a href="javascript:void(0)" class="easyui-linkbutton" onclick="acode_search()">检索</a>
            </td>
        </tr>
        <tr>
            <td>
                核算码名称：
            </td>
            <td>
                <input id="acode_name" name="acode_name" type="text" style="width: 400px" readonly="readonly" />
            </td>
        </tr>
        <tr>
            <td>
                预算金额：
            </td>
            <td>
                <input id="amount" name="amount" type="text" style="width: 100px" onkeyup="dxamount.value=convertCurrency(amount.value);" />
                <input id="dxamount" name="dxamount" style="width: 290px" readonly="readonly" />
            </td>
        </tr>
        <tr>
            <td>
            </td>
            <td style="text-align: right;">
                <input id="sumbit" name="submit" type="submit" value=" 提交 " />
            </td>
        </tr>
    </table>
    </form>Budget.ashx
        public void ProcessRequest(HttpContext context)
        {
            context.Response.ContentType = "text/plain";
            var action = context.Request["action"];
            context.Response.Write(action);
        }