Transmission of springmvc values (from foreground to background)

//About parameter transfer acceptance

If there is this tag on the @RequestBody method, the front-end parameters (ajax) are both attribute-driven, model-driven, passed to the backend, and written on the method name, only a pair of images can be passed, not a list (so The parameter data passed by ajax can only be {}), and it can be a list written on the parameter (this is data can be [{}{}]). Use [] to declare that it is a complex format json, see below for details.
This label method returns the data of the callback function

@RequestMapping(value = "/savemobile")
@RequestBody
    public int saveMobile(@RequestBody List<User> user ,@RequestParam(value = "yzm", required = false) String yzm ) {
@RequestMapping(value = "/savemobile")//
    public int saveMobile(@RequestBody List<User> user ,@RequestParam(value = "yzm", required = false) String yzm) {
@RequestMapping( value = "/savemobile")//This can be
@RequestBody
    public int saveMobile(@RequestBody List<User>

    @ResponseBody//这种可以
    public String saveMobile(@RequestParam(value = "yzm", required = false) String yzm , User user ) {

   @ResponseBody//卸载外面的时候里面的只能是单个实体
    public PageInfo<Role> queryPageSupplier(HttpSession session,
    @RequestParam(value = "pageNo", required = false) int pageNo,
                                            @RequestParam(value = "pageSize", required = false) int pageSize,
                                            Role role)




    @RequestMapping(value = "/savemobile")
    @ResponseBody
    public String saveMobile(@RequestParam(value = "yzm", required = false) String yzm , User user ) {
$.ajax({

            type: "post",
            url: "<%=webPath%>/system/users/savemobile.do",
            data: ndata,
            dataType: "json",
///////////////////// //////// contentType: "application/json", this sentence goes without list [] is a complex format flag
            success: function (data) {
                if (data = 1) {
                alert("Binding is successful, Thank you!");
                } else if (data = 0) {
                    alert("The operation failed, the record may no longer exist.");
                } else if (data > 1) {
                    alert("Error, multiple records were deleted .");
                }
            },
            error: function (textStatus) {
                alert("Data load failed!!!");
            }
});


========复杂格式json提交=========================
@RequestMapping(value = "/savetree")
    public String saveTree( @RequestBody List<MenuDto>  menuDtos, @RequestParam(value = "roleId", required = false) String roleId) {

$.ajax({
            type: "post",
            url: "<%=webPath%>/system/acount/savetree.do?roleId="+roleId,
            data: JSON.stringify(events),
            dataType: "json",
            contentType:"application/json"
           
        });


@RequestMapping(value = "/savecheck")
    @ResponseBody
    public String saveCheck(@RequestBody List<User> user) {//由于前台是【】不是{}
    System.out.println("111");
        return "redirect:index.do";
    }


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