1.背景

事情是这样的。ftl页面里有一个动态的表格，表格里面的数据是用ftl表达式遍历一个list得到的数据，类似这样：

...
<tbody>
<#list peopleList as people>
    <tr>
        <td>${people.id}</td>
        <td>${people.address}</td>
        <td>${people.name}</td>
    </tr>
</#list>
</tbody>
...

2.需求

现在需求是，点击保存按钮时将表格里面的数据传到后台，存入数据库中。

3.前端代码

我们在JavaScript代码中嵌套ftl表达式，通过ajax将数据传到后台，请求后台方法。

$(document).on("click", '#Button_Save', function () {
        var peopleList = new Array();//声明一个数组
        var peopleListSize = "${peopleList?size}";
        if(peopleListSize != 0){
            var j = 0;
            <#list peopleList as people>
                j++;
                var people= ${people};
                peopleList.push(people);
            </#list>
        }
        $.ajax({
            type: "POST",
            url: contextPath + "/operation/add/",
            data: {"peopleList":JSON.stringify(peopleList)},
            dataType: "json",
            success: function (data) {
                if (data.resultCode == 0) {
                    //成功
                    alert("保存成功");
                } else {
                    //错误
                    alert(data.resultData);
                }
            },
            error: function (data) {
                $("#operationButtonList").show();
                alert("请求失败！");
            }
        });
    });

4.后端代码

后台代码就是接收这个list并将其存到数据库，有一点注意的是，我们在向后台传数据的时候，不能够直接传这个list，在这里我用了一个JSON.stringify（）函数，在后台我们直接用String类型参数来接收。

   @PostMapping("/add")
   @ResponseBody
   public JSONObject updatePeopleInfo(@RequestParam String peopleList, HttpServletRequest request) {
       List<People> peopleList = new ArrayList<People>();
       peopleList= JSON.parseArray(peopleList, People.class);
       for(People people: peopleList){
        People peopleInfo= new People();
        peopleInfo.setId(people.getId());
        peopleInfo.setAddress(people.getAddress());
        peopleInfo.setName(people.getName());
            peopleMapper.updateByPrimaryKeySelective(peopleInfo);
       }

       logger.info("peopleInfo:{}", peopleInfo);
       JSONObject result = ResponseUtil.packSuccessResult("保存成功");
       return result;
   }