$(document).ready(function () {

 var schoolList={
  "pageCount": "2",
  "pageIndex": "1",
  "sign": "1",
  "uniPayId": "9dc1308bab2b4b49987a0c12dd7339f5"
}
 $.ajax({
        type:"POST",
        url:"/schoolroll/insert",
        contentType: "application/json", //必须这样写
        dataType:"json",
        data:JSON.stringify(schoolList),//schoolList是你要提交是json字符串
        success:function (data) {

        }

    })
})

后台对应的controller

对应的实体类信息：

这样能够实现，前台传递json数据，后台用实体类接收参数，将数据值映射到对应的字段上面