function show() {
    $.ajax({
        type: "post",
        async: false,
        contentType: "application/json",
        url: "/WebForm1.aspx/GetStr",
        data: '{"name":"txxx"}',
        dataType: "json",
        success: function (result) {
            debugger;
            var data = $.parseJSON(result.d);
            alert(data.name);
        }
    });
}

[WebMethod]
public static string GetStr(string name)
{
　　return "{\"name\":\"" + name + "\"}";
}

$.ajax({
        type: 'post',
        url: '/Test/FormParas',
        data: { para1: 'p1', para2: 'p2' },
        contentType: 'application/x-www-form-urlencoded',
        dataType: 'json',// 響應類型
        success: function (res) {
            console.log(res);
        },
        error: function () {
            alert('程序出錯');
        },
        beforeSend: function () {
            // 加載loading框
        },
        complete: function () {
            // 關閉loading框
        }
    });


[HttpPost]
        public IActionResult FormParas([FromForm] string para1, [FromForm] string para2)
        {
            return Json(new { code = 0, msg = $"接收到的參數 para1:{para1},para2:{para2}" });
        }