在debug过程中走到if判断的时候，判断完直接跳出到base.py，后面的语句都没有执行。

下面是js代码

{% block custom_js %}
<script type="text/javascript">
    //添加评论
    $('#js-pl-submit').on('click', function(){
        var comments = $("#js-pl-textarea").val()
        if(comments == ""){
            alert("评论不能为空")
            return
        }
        $.ajax({
            cache: false,
            type: "POST",
            url:"{% url 'course:add_comment' %}",
            data:{'course_id':{{ course.id }}, 'comments':comments},
            async: true,
            beforeSend:function(xhr, settings){
                xhr.setRequestHeader("X-CSRFToken", "{{ csrf_token }}");
            },
            success: function(data) {
                if(data.status == 'fail'){
                    if(data.msg == '用户未登录'){
                        window.location.href="/login/";
                    }else{
                        alert(data.msg)
                    }

                }else if(data.status == 'success'){
                    window.location.reload();//刷新当前页面.
                }
            },
        });
    });

</script>
{% endblock %}