CSRF保护True和ajax代码无法正常工作

Question

我在config.php中有CSRF保护True。 单击标准/类名称后，ajax请求无效。

请帮帮我，谢谢。

查看代码：

<?php echo form_open('admin/Teacher/add_teacher_by_subject') ?>
<div class="form-group">
        <label>Standard / Class Name<span class="text-danger">*</span></label>
        <select class="form-control" name="standard_name" id="standard_name" style="width: 100%;">
            <option value="">----Select Standard / Class----</option>
            <?php foreach ($standard as $value): ?>
                <option value="<?php echo $value['standard_id'] ?>"><?php echo $value['standard_name']; ?></option>
            <?php endforeach; ?>
        </select>
    </div>
    <div class="form-group">
        <label>Section<span class="text-danger">*</span></label>
        <select class="form-control" name="section_name" id="section_name" style="width: 100%;">

        </select>
    </div>
<?php form_close() ?>

AJAX代码：

<script>
    $(document).ready(function () {

        $('#standard_name').change(function () {
            var standard_id = $('#standard_name').val();
            if (standard_id != "") {
                var post_url = base_url + "admin/Teacher/get_section_name/" + standard_id;
//                console.log(standard_id);
                $.ajax({
                    type: "POST",
                    url: post_url,
                    success: function (result)
                    {
                        var obj = JSON.parse(result);
                        var options = "";
                        options = "<option value=''>----Select Section / Division----</option>";
                        for (x in obj) {
                            options += "<option value='" + obj[x].section_id + "'>" + obj[x].section_name + "</option>";
                        }
                        document.getElementById("section_name").innerHTML = options;
                    } //end success
                }); //end AJAX
            }
        });
});
</script>