返回JSON数据

<button type="submit"  id="quety" class="btn btn-info" onclick="query()">查询</button>

<script>
 function query()
    {

        $.ajax(
            {
                url:"/hello/data",
                data:{},
                type:"post",
                dataType:"json",
                success:function(data)
                {
                    alert("数据: " + JSON.stringify(data) + "\n状态: " + status);
                },
                error: function() {
                    alert("error");
                }
            });
    }
</script>

后台

@Controller
@RequestMapping("/hello")
public class HelloController {


    @Autowired
    private UserMapper userMapper;

    @RequestMapping(value = "/data", method = RequestMethod.POST)
    @ResponseBody
    public List<User> data() {
        List<User> list = new ArrayList<User>();
      list=userMapper.findAll();
        return list;
    }
    }

默认ajax是异步的,数据的接受和下面方面的执行，不产生冲突。

图片.png
参考:
https://blog.csdn.net/Handsome2013/article/details/89809962
https://blog.csdn.net/qq_19301269/article/details/78588792