Android 客户端调用后台,以前用过 ksoap2 调用 wcf 。
最近把后台改成 WebAPI ,客户端向后台传参数、文件时碰到些问题:
一、传参数
用 JQuery ajax 调用后台方法时,后台方法一般定义成这样:
[WebMethod] [Authorize] public string GetCustomList(string CustomerName, string Name, string Loc_Name, string selectStorageState) { }
前台这样调用:
$.ajax({ type: "POST", url: "/Home/GetCustomList", data: "{ \"CustomerName\":\"" + $("#CustomerName").val() + "\",\"Name\": \"" + $("#Name").val() + "\",\"Loc_Name\": \"" + $("#Loc_Name").val() + "\",\"selectStorageState\": \"" + $("#selectStorageState").val() + "\" }", contentType: "application/json; charset=utf-8", dataType: "json", success: function (msg) { }, error: function (xhr, msg) { alert(msg); } });
用这种方法传参在 WebAPI 里会报下面的错误:
Can’t bind multiple parameters (‘foo’ and ‘bar’) to the request’s content.
可以有以下方法解决这个报错
1、后台封装成类
WebAPI 后台:
public class User { public string user_name { get; set; } public string user_password { get; set; } }
[HttpPost] public string Login([FromBody]User user) { }
Android 前台:
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(); nameValuePairs.add(new BasicNameValuePair("user_name", mUserName)); nameValuePairs.add(new BasicNameValuePair("user_password", mPassword)); String resultString=""; try { resultString= HttpHelper.invokePost("Login", nameValuePairs); } catch (Exception e) { }
2、拼 json
WebAPI 后台
[HttpPost] [Authorize] public string GetStockList([FromBody]string jsonString) { JObject jObject = JObject.Parse(jsonString); page = Convert.ToInt32(jObject["page"].ToString()); pageSize = Convert.ToInt32(jObject["pageSize"].ToString()); }
Android 前台
String jsonString = "{\"page\":\""+sPage+"\",\"pageSize\":\""+sPageSize+"\"}"; List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(); nameValuePairs.add(new BasicNameValuePair("", jsonString)); String resultString= HttpHelper.invokePost("GetStockList", nameValuePairs);
二、传文件
WebAPI 后台
[Authorize] public Task<HttpResponseMessage> Add_Img() { string root = HttpContext.Current.Server.MapPath("~"); string tmpRoot = root + "/App_Data"; var provider = new MultipartFormDataStreamProvider(tmpRoot); // Read the form data and return an async task. // 读取表单数据,并返回一个async任务 string sName = "88"; string nName = ""; string FilePath = "Uploads/"; Request.Content.Headers.ContentType.CharSet = "UTF-8"; var task = Request.Content.ReadAsMultipartAsync(provider). ContinueWith<HttpResponseMessage>(t => { sName = provider.FileData[0].LocalFileName; string GpsImgJson = provider.FormData["GpsImgJson"]; GpsImgJson = HttpUtility.UrlDecode(GpsImgJson, Encoding.GetEncoding("UTF-8")); GpsImg gpsImg = JsonHelper.JsonDeserialize<GpsImg>(GpsImgJson); nName = gpsImg.FileName; FilePath += nName; if (!File.Exists(root + "/" + FilePath)) { File.Move(sName, root + "/" + FilePath); } //保存 if (true) { return Request.CreateResponse<string>(HttpStatusCode.OK, "上传成功"); } else { return Request.CreateResponse<string>(HttpStatusCode.InternalServerError, "保存出错!"); } }); return task; }
Android 前台
String jsonString = "{\"Title\":\""+myTitleText.getText().toString()+ "\",\"Content\":\""+myContentText.getText().toString()+ "\",\"FileName\":\""+filename+ "\",\"Longitude\":\""+lonString+"\",\"Latitude\":\""+latString+"\"}"; Map<String, String> params0 = new HashMap<String, String>(); params0.put("GpsImgJson", jsonString); String st= HttpHelper.invokePost("AddImg", mImageUri.getPath(), params0);
public static String invokePost(String action, String filePath, Map<String, String> params) { try { String url = API_URL + action + "/"; Log.d(TAG, "url is" + url); HttpPost httpPost = new HttpPost(url); File file = new File(filePath); MultipartEntity reqEntity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE,null,Charset.forName("UTF-8")); FileBody fb = new FileBody(file); reqEntity.addPart("myFile", fb); if(params != null){ Iterator<String> it = params.keySet().iterator(); while(it.hasNext()){ String name = it.next(); reqEntity.addPart(name, new StringBody(params.get(name),Charset.forName("UTF-8"))); } } httpPost.setEntity(reqEntity); return invoke(httpPost); } catch (Exception e) { Log.e(TAG, e.toString()); } return null; }
参考网页:
http://encosia.com/using-jquery-to-post-frombody-parameters-to-web-api/