小程序：

wx.request({

url: 'http://localhost:63026/api/News/Uploaddata',

method: 'post',

data: "123",

header: {

"Content-Type": "application/x-www-form-urlencoded"

},

success: function (res) {

console.log(res)

}

})

后台：

[HttpPost]

        public string  Uploaddata([FromBody]object value)

        {

            string name = HttpContext.Current.Request["data"];

            return "success2";

        }