从android将新数据放入Server

Question

我想使用android-volley编辑我的Server数据，我尝试使用请求方法put更新我的db，并将数据更改为JSON，并使用visual studio捕获JSON，最后更改Server数据。

安卓工作室：

StringRequest stringRequest = new StringRequest(Request.Method.PUT,
                    url, new Response.Listener<String>() {

            @Override
            public void onResponse(String response) {     
                Log.d("success", response);
                Toast.makeText(SystemActivity.this, "succesful!, Toast.LENGTH_SHORT).show();
            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                Log.d("error", error.toString());
            }
        });


        getparams();

        mQueue.add(stringRequest);
        //put-volley

    }

    //put-volley

    protected Map<String, String> getparams() {
        Map<String, String> params = new HashMap<String, String>();
        params.put("NotesID", corusername);  //NotesID
        params.put("Password", renewpass);

        return params;
    }
    //put-volley

视频工作室：

public HttpResponseMessage Put(string userID, [FromBody] Account account)
{
    try
    {
        using (DemoEntities entities = new DemoEntities())
        {
            var entity = entities.Account.FirstOrDefault(s => s.NotesID == userID);

            if (entity == null)
            {
                return Request.CreateErrorResponse(HttpStatusCode.NotFound, "customers with userid = " + userID + "is not found");
            }
            else
            {
                entity.NotesID = account.NotesID;
                entity.Password = account.Password;

                entities.SaveChanges();
                return Request.CreateResponse(HttpStatusCode.OK, entity);
            }

        }
    }
    catch (Exception ex)
    {
        return Request.CreateErrorResponse(HttpStatusCode.BadRequest, ex);
    }
}

Answer 1

正如我所看到的，您正在StringRequest之外调用StringRequest()：

getparams(); 
mQueue.add(stringRequest);

相反，您需要在StringRequest作用域中覆盖它，例如：

StringRequest stringRequest = new StringRequest(Request.Method.PUT, url,
            new Response.Listener<String>() {
                @Override
                public void onResponse(String response) {
                    //Response
                }
            },
            new Response.ErrorListener() {
                @Override
                public void onErrorResponse(VolleyError error) {
                    //Error
                }
            }) {
        @Override
        protected Map<String, String> getParams() throws AuthFailureError {
            Map<String, String> params = new HashMap<String, String>();
                params.put("NotesID", corusername);  //NotesID
                params.put("Password", renewpass);

                return params;
        }
        @Override
        public HashMap<String, String> getHeaders() {
                HashMap headers = new HashMap();
                headers.put("Content-Type", "application/json");
                return headers;
        }
};

//Add request to volley request queue
VolleyRequestQueue.getInstance().addToRequestQueue(stringRequest);

另外，HTTP 400可能是因为标头内容类型设置错误。因此，您必须在StringRequest overriden方法中设置标题，如：

@Override
public HashMap<String, String> getHeaders() {
        HashMap headers = new HashMap();
        headers.put("Content-Type", "application/json");
        return headers;
}

另外，为了正确地将JSON绑定到您的操作，您修改了操作以在参数中包含属性FromBody。因此，您必须在请求中定义正确的标题：

contentType:"application/json"
//or
headers.put("Content-Type", "application/json");

也要先在邮递员中测试你的投递请求。