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How to download the file using ASP.NET MVC Rest API call and jQuery Ajax

I am using ASP.NET MVC calling REST API to download the file (any type). I am not sure how do i show in browser download the file directly.
The file might be any format either pdf/image/excel/word/ etc.
Here is my code from jQuery, controller and REST API call.
Please help me how do I send back file data from REST API --> controller --> jQuery?
jQuery Ajax Call. This is onclick event on a table
//JQuery Ajax call to 'GetDocument'
$("#DivAttachmentDetails td ").click(function () {
var DocumentumId = $('#hdnDocumentumId').val();
$.ajax({
type: 'POST',
url: getExactPath('/Supplier/GetDocument'),
data: {
documetObj: DocumentumId
},
dataType: 'json',
async: false,
success: function (jsonData) {
//alert('Hello');
},
error: function () {
alert("Unable to fetch the Document.");
}
});
});
Controller method called from jQuery:
//Method in the Controller called from jQuery Ajax.
public JsonResult GetDocument(string documetObj)
{
DocumentumUtil dUtil = new DocumentumUtil();
String dId;String fileName;String fileExt;String doc = "";
String applicationType = "";
String[] docum;
docum = documetObj.Split(':');
dId = docum[0];
fileName = docum[1].Substring(0, docum[1].LastIndexOf('.'));
fileExt = docum[2];
try
{
String contenType = dUtil.getFileContentType(dId); // Fetch the file content type based on DocumentumId
doc = dUtil.getDocument(dId, fileName, contenType);
}
catch(System.Exception ex) {}
return this.Json("", JsonRequestBehavior.AllowGet);
}
This the REST API call:
// This is the method i am calling from Controller -GetDocument()
public String getDocument(String documentId, String fileName, String contenType)
{
_httpClient = new HttpClient();
D2Document newDocument = new D2Document();
newDocument.SetPropertyValue("object_name", fileName);
newDocument.SetPropertyValue("a_content_type", contenType);
String documentURL = ConfigurationManager.AppSettings["DOCUMENTUM_URL"] + "objects/"+ documentId + "/content-media?format=" + contenType + "&modifier=&page=0";
JSON_GENERIC_MEDIA_TYPE = new MediaTypeWithQualityHeaderValue("application/json");
JSON_VND_MEDIA_TYPE = new MediaTypeWithQualityHeaderValue("application/vnd.emc.documentum+json");
try
{
using (var multiPartStream = new MultipartFormDataContent())
{
String encoded = System.Convert.ToBase64String(System.Text.Encoding.GetEncoding("ISO-8859-1").GetBytes(username + ":" + password));
request.Headers.Add("Authorization", "Basic " + encoded);
var credentials = Convert.ToBase64String(Encoding.ASCII.GetBytes(string.Format("{0}:{1}", username, password)));
_httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", credentials);
using (HttpResponseMessage response = _httpClient.GetAsync(documentURL).Result)
{
if (response != null)
{
var responsestream = response.Content;
}
}
}
}
}
How do I convert the content to stream/bytes?

Here is the code i have converted to file stream.
using (HttpResponseMessage response = _httpClient.GetAsync(documentURL).Result)
{
if (response != null)
{
HttpContent content = response.Content;
//Get the actual content stream
Stream contentStream = content.ReadAsStreamAsyn().Result;
//copy the stream to File Stream. "file" is the variable have the physical path location.
contentStream.CopyTo(file);
}
}

Ajax call web API successful but C# call web API 404 not found

I have these web API methods:
[System.Web.Http.RoutePrefix("api/PurchaseOrder")]
public class PurchaseOrderController : ApiController
{
private static ILog logger = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
[System.Web.Http.Route("PagingCriticalPart")]
[System.Web.Http.HttpPost]
public JsonResult PagingCriticalPart([FromBody] Helper.DataTablesBase model)
{
logger.Info("PagingCriticalPart");
JsonResult jsonResult = new JsonResult();
try
{
if (model == null) { logger.Info("model is null."); }
int filteredResultsCount;
int totalResultsCount;
var res = BLL.PurchaseOrderHandler.PagingCriticalPart(model, out filteredResultsCount, out totalResultsCount);
var result = new List<Models.T_CT2_CriticalPart>(res.Count);
foreach (var s in res)
{
// simple remapping adding extra info to found dataset
result.Add(new Models.T_CT2_CriticalPart
{
active = s.active,
createBy = s.createBy,
createdDate = s.createdDate,
id = s.id,
modifiedBy = s.modifiedBy,
modifiedDate = s.modifiedDate,
partDescription = s.partDescription,
partNumber = s.partNumber
});
};
jsonResult.Data = new
{
draw = model.draw,
recordsTotal = totalResultsCount,
recordsFiltered = filteredResultsCount,
data = result
};
return jsonResult;
}
catch (Exception exception)
{
logger.Error("PagingCriticalPart", exception);
string exceptionMessage = ((string.IsNullOrEmpty(exception.Message)) ? "" : Environment.NewLine + Environment.NewLine + exception.Message);
string innerExceptionMessage = ((exception.InnerException == null) ? "" : ((string.IsNullOrEmpty(exception.InnerException.Message)) ? "" : Environment.NewLine + Environment.NewLine + exception.InnerException.Message));
jsonResult.Data = new
{
draw = model.draw,
recordsTotal = 0,
recordsFiltered = 0,
data = new { },
error = exception.Message
};
return jsonResult;
}
}
[System.Web.Http.Route("UploadRawMaterialData")]
[System.Web.Http.HttpPost]
public JsonResult UploadRawMaterialData(string rawMaterialSupplierData)
{
JsonResult jsonResult = new JsonResult();
jsonResult.Data = new
{
uploadSuccess = true
};
return jsonResult;
}
}
When use ajax to call PagingCriticalPart, no issue.
"ajax": {
url: 'http://localhost/ControlTower2WebAPI/api/PurchaseOrder/PagingCriticalPart',
type: 'POST',
contentType: "application/json",
data: function (data) {
//debugger;
var model = {
draw: data.draw,
start: data.start,
length: data.length,
columns: data.columns,
search: data.search,
order: data.order
};
return JSON.stringify(model);
},
failure: function (result) {
debugger;
alert("Error occurred while trying to get data from server: " + result.sEcho);
},
error: function (XMLHttpRequest, textStatus, errorThrown) {
debugger;
alert("Error occurred while trying to get data from server!");
},
dataSrc: function (json) {
//debugger;
for (key in json.Data) { json[key] = json.Data[key]; }
delete json['Data'];
return json.data;
}
}
But when call UploadRawMaterialData from c#, it get error: 404 not found.
var data = Newtonsoft.Json.JsonConvert.SerializeObject(rawMaterialVendorUploads);
string apiURL = #"http://localhost/ControlTower2WebAPI/api/PurchaseOrder/UploadRawMaterialData";
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(apiURL);
request.UseDefaultCredentials = true;
request.Method = "POST";
request.ContentType = "application/json";
request.ContentLength = data.Length;
using (Stream webStream = request.GetRequestStream())
using (StreamWriter requestWriter = new StreamWriter(webStream, System.Text.Encoding.ASCII))
{
requestWriter.Write(data);
}
try
{
WebResponse webResponse = request.GetResponse();
using (Stream webStream = webResponse.GetResponseStream() ?? Stream.Null)
using (StreamReader responseReader = new StreamReader(webStream))
{
string response = responseReader.ReadToEnd();
}
}
catch (Exception exception)
{
}
using postman return similar error:
{
"Message": "No HTTP resource was found that matches the request URI 'http://localhost/ControlTower2WebAPI/api/PurchaseOrder/UploadRawMaterialData'.",
"MessageDetail": "No action was found on the controller 'PurchaseOrder' that matches the request."
}
But if I use postman to call it like this, no issue:
http://localhost/ControlTower2WebAPI/api/PurchaseOrder/UploadRawMaterialData?rawMaterialSupplierData=test
What am I missing?

In your method signature for the UploadRawMaterialData method you are missing the [FromBody] attribute. All POST requests with data in the body need this

You have two options,
Use [FromBody] as suggested in other answer,
Make your Url like this.
string queryData="test"
string apiUrl="http://localhost/ControlTower2WebAPI/api/PurchaseOrder/UploadRawMaterialData?rawMaterialSupplierData="+test;
Basically,
The way you are sending your query data is all that matters, If you don't specify [FromBody] attribute, the data is passed in the URI and URI has to be modified.

C# Xamarin Android Rest call in PCL error "Unexpected character encountered while parsing value: S. Path '', line 0, position 0."

I have used SO to help with several issues in the past. However, I cannot find a solution to something I have been struggling with for 2 days now.
I am a noob, please be kind :)
I have an app that I created using Xamarin Studio, targeted for Android. It is a basic GET request from a Rest Api. It was working perfectly until I realized I was not helping myself when it came time to create the same app in IOS and Windows. Once I changed my project to utilize a PCL I started getting errors, primarily around my RestClient class (originally got from http://www.codeproject.com/Tips/497123/How-to-make-REST-requests-with-Csharp)
From my droid app class:
var apiUser = GetString(Resource.String.apiUser);
var apiPass = GetString(Resource.String.apiPass);
//Get token from API
string token = authenticate(apiUser,apiPass);
public static string authenticate(string apiUser, string apiPass)
{
Authentication Auth = new Authentication ();
try
{
// set json by passing AuthenticationUrl as endpoint, returns json data
var o = JObject.Parse(EntryRepository.getJson(PJTApiUrls.getAuthenticationUrl(apiUser,apiPass)));
Auth.Token = (string)o["Token"];
return Auth.Token;
}
catch (Exception e)
{
// Couldn't do stuff. Log the exception.
// TODO possible timeout, try again, if fails again then return error message
if (e.Message.Contains("400") || e.Message.Contains("401"))
{
string error = string.Format("Invalid credentials, please try again");
return error;
} else {
string error = string.Format ("An error occurred: \r\n{0}", e.Message);
return error;
}
}
}
getAuthenticationUrl gets the api URL.
Here is getJson (in PCL):
public static string getJson(string endpoint)
{
string apiurl = endpoint;
var client = new _RestClient();
client.EndPoint = apiurl;
client.ContentType = "application/json";
client.Method = HttpVerb.GET;
//client.Method = HttpVerb.POST;
client.PostData = "";
//client.PostData = "{postData: value}";
//client.PostData = "{'someValueToPost': 'The Value being Posted'}";
var json = client._MakeRequestAsync();
// to append parameters, pass them into make request:
//var json = client.MakeRequest("?param=0");
return json.ToString();
}
And for the _RestClient class (in PCL):
public async Task<string> _MakeRequestAsync()
{
try {
var request = _MakeRequestAsync ("");
return await request;
}
catch (Exception e){
return e.Message;
}
}
public async Task<string> _MakeRequestAsync(string parameters)
{
var uri = new Uri(EndPoint + parameters);
var request = WebRequest.Create(uri) as HttpWebRequest;
using (var response = await request.GetResponseAsync () as HttpWebResponse) {
var responseValue = string.Empty;
if (response.StatusCode != HttpStatusCode.OK) {
var message = String.Format ("Request failed. Received HTTP {0}", response.StatusCode);
throw new Exception (message);
}
// grab the response
using (var responseStream = await Task.Factory.FromAsync<Stream>(request.BeginGetRequestStream, request.EndGetRequestStream, null)) {
//using (var responseStream = response.GetResponseStream ()) {
if (responseStream != null)
using (var reader = new StreamReader (responseStream)) {
responseValue = reader.ReadToEnd ();
}
}
return responseValue;
}
}
responseValue is returning null
return await request is saying "Status = Waiting for activation"
I have also had the error: "Unexpected character encountered while parsing value: S. Path '', line 0, position 0."
But this works if the RestClient class is within Droid (Instead of the shared PCL) and contains the following:
public string MakeRequest ()
{
return MakeRequest ("");
}
public string MakeRequest (string parameters)
{
var request = (HttpWebRequest)WebRequest.Create (EndPoint + parameters);
request.Method = Method.ToString ();
request.ContentLength = 0;
request.ContentType = ContentType;
if (!string.IsNullOrEmpty (PostData) && Method == HttpVerb.POST) {
var bytes = Encoding.GetEncoding ("iso-8859-1").GetBytes (PostData);
request.ContentLength = bytes.Length;
using (var writeStream = request.GetRequestStream ()) {
writeStream.Write (bytes, 0, bytes.Length);
}
}
using (var response = (HttpWebResponse)request.GetResponse ()) {
var responseValue = string.Empty;
if (response.StatusCode != HttpStatusCode.OK) {
var message = String.Format ("Request failed. Received HTTP {0}", response.StatusCode);
throw new ApplicationException (message);
}
// grab the response
using (var responseStream = response.GetResponseStream ()) {
if (responseStream != null)
using (var reader = new StreamReader (responseStream)) {
responseValue = reader.ReadToEnd ();
}
}
return responseValue;
}
}
I cannot figure this out, any help/guidance is appreciated. Let me know if I can clarify anything.
***** UPDATE ***** Thanks to #milen-pavlov help thus far, here is where I am currently at:
in Android project:
var apiUser = GetString(Resource.String.apiUser);
var apiPass = GetString(Resource.String.apiPass);
//Get token from API
var token = await authenticate(apiUser,apiPass);
lblOutput.Text = token;
calls (also in Android project):
public static async Task<string> authenticate(string apiUser, string apiPass)
{
Authentication Auth = new Authentication ();
try
{
// set json by passing AuthenticationUrl as endpoint, returns json data
var o = JObject.Parse(await EntryRepository.getJson(PJTApiUrls.getAuthenticationUrl(apiUser,apiPass)));
Auth.Token = (string)o["Token"];
return Auth.Token;
}
catch (Exception e)
{
if (e.Message.Contains("400") || e.Message.Contains("401"))
{
string error = string.Format("Invalid credentials, please try again");
return error;
} else {
string error = string.Format ("An error occurred: \r\n{0}", e.Message);
return error;
}
}
}
Calls json class in PCL project:
public static async Task<string> getJson(string endpoint)
{
string apiurl = endpoint;
var client = new _RestClient();
client.EndPoint = apiurl;
client.ContentType = "application/json";
client.Method = HttpVerb.GET;
client.PostData = "";
var json = await client._MakeRequestAsync();
return json;
}
which then calls restclient class in PCL project:
public async Task<string> _MakeRequestAsync()
{
var request = _MakeRequestAsync ("");
return await request;
}
public async Task<string> _MakeRequestAsync(string parameters)
{
var uri = new Uri(EndPoint + parameters);
using (var client = new HttpClient())
{
var response = await client.GetAsync(uri);
return await response.Content.ReadAsAsync<string>();
};
}
End result/error:
Any guidance is appreciated!

Can you use HttpClient instead?
Sample Get request will look similar to this:
public async Task<string> _MakeRequestAsync(string parameters)
{
var uri = new Uri(EndPoint + parameters);
using (var client = new HttpClient())
{
var response = await client.GetAsync(uri);
return await result.Content.ReadAsStringAsync();
};
}

How to Send POST Request in windows Phone 8 and get its Response in json

I am trying to call a web service
which returns a JSON response. So far my code is working fine for GET Request but now services on server are POST and I have no idea how to do that! Below is the code for GET Request:
private void callSigninWebservice()
{
setProgressIndicator(true);
SystemTray.ProgressIndicator.Text = "Signing in please wait";
try
{
WebClient webClient = new WebClient();
Uri uri = new Uri(GlobalVariables.URL_USER +
GlobalVariables.URL_STUDENT_SIGNIN_MODE_LOGIN +
GlobalVariables.URL_EMAIL + tbUsername.Text +
GlobalVariables.URL_PASSWORD + tbPassword.Password);
webClient.DownloadStringCompleted += new DownloadStringCompletedEventHandler(webClient_DownloadStringCompleted);
webClient.DownloadStringAsync(uri);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message + "error came here 1");
}
}
For Response
void webClient_DownloadStringCompleted(object sender, DownloadStringCompletedEventArgs e)
{
try
{
JObject parentObj = JObject.Parse(e.Result);
String strResult = (String)parentObj[SigninData.JSON_result];
bool bolresult = strResult.Equals(SigninData.JSON_result_success, StringComparison.Ordinal);
if (bolresult)
{
JObject dataObj = (JObject)parentObj[SigninData.JSON_data];
setUserData(dataObj);
NavigationService.Navigate(new Uri("/BasePage.xaml", UriKind.RelativeOrAbsolute));
}
else
{
String error = (String)parentObj[SigninData.JSON_data];
MessageBox.Show("Error : " + error);
}
setProgressIndicator(false);
}
catch (Exception)
{
setProgressIndicator(false);
}
}

This is a simple way of making a post request and receiving a response in JSON for future parse:
internal static async Task<String> GetHttpPostResponse(HttpWebRequest request, string postData)
{
String received = null;
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
byte[] requestBody = Encoding.UTF8.GetBytes(postData);
// ASYNC: using awaitable wrapper to get request stream
using (var postStream = await request.GetRequestStreamAsync())
{
// Write to the request stream.
// ASYNC: writing to the POST stream can be slow
await postStream.WriteAsync(requestBody, 0, requestBody.Length);
}
try
{
// ASYNC: using awaitable wrapper to get response
var response = (HttpWebResponse)await request.GetResponseAsync();
if (response != null)
{
var reader = new StreamReader(response.GetResponseStream());
// ASYNC: using StreamReader's async method to read to end, in case
// the stream i slarge.
received = await reader.ReadToEndAsync();
}
}
catch (WebException we)
{
var reader = new StreamReader(we.Response.GetResponseStream());
string responseString = reader.ReadToEnd();
Debug.WriteLine(responseString);
return responseString;
}
return received;
}

Post string and bytearray to server

I have done POSTING and GETing from server using string post data, but now i have the next WebService:
submitFeedback(String token, String subject, String body, byte[] photo, byte[] video);
private void PostFeedbackData()
{
if (GS.online != true)
{
MessageBox.Show(GS.translations["ErrorMsg0"]);
}
else
{
HttpWebRequest request = HttpWebRequest.CreateHttp("https://****/feedback");
request.Method = "POST";
request.BeginGetRequestStream(new AsyncCallback(GetRequestStreamCallback), request);
}
}
void GetRequestStreamCallback(IAsyncResult callbackResult)
{
HttpWebRequest myRequest = (HttpWebRequest)callbackResult.AsyncState;
// End the stream request operation
Stream postStream = myRequest.EndGetRequestStream(callbackResult);
// Create the post data
string postData = "";
Deployment.Current.Dispatcher.BeginInvoke(() =>
{
postData = "{\"jsonrpc\": \"2.0\", \"method\": \"getUserSchedule\", \"params\":[" + "\"" + (App.Current as App).UserToken + "\",\"" + FeedbackTitle.Text + "\",\"" + FeedbackContent.Text + "\",\"" + imageBytes + "\"], \"id\": 1}";
byte[] byteArray = Encoding.UTF8.GetBytes(postData);
// Add the post data to the web request
postStream.Write(byteArray, 0, byteArray.Length);
postStream.Close();
// Start the web request
myRequest.BeginGetResponse(new AsyncCallback(GetResponsetStreamCallback), myRequest);
});
}
Look at post data - it is a string, i can't place there imageBytes array. How to do it?

Is there any reason for using HttpWebRequest ?
I am asking that because i think that the correct way of sending files to a service is by multipartform data. With HttpWebRequest you have to manually implement that.
Here is an example that is using Microsoft's HttpClient that might work for you:
public async Task<string> submitFeedback(String token, String subject, String body, byte[] photo, byte[] video) {
var client = new HttpClient();
var content = new MultipartFormDataContent();
// Some APIs do not support quotes in boundary field
foreach (var param in content.Headers.ContentType.Parameters.Where(param => param.Name.Equals("boundary")))
param.Value = param.Value.Replace("\"", String.Empty);
var tok = new StringContent(token);
content.Add(tok, "\"token\"");
var sub = new StringContent(subject);
content.Add(tok, "\"subject\"");
// Add the Photo
var photoContent = new StreamContent(new MemoryStream(photo));
photoContent.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data")
{
Name = "\"photo\"",
FileName = "\"photoname.jpg\""
};
photoContent.Headers.ContentType = MediaTypeHeaderValue.Parse("image/jpeg");
content.Add(photoContent);
// Add the video
var videoContent = new StreamContent(new MemoryStream(video));
videoContent.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data")
{
Name = "\"video\"",
FileName = "\"videoname.jpg\""
};
videoContent.Headers.ContentType = MediaTypeHeaderValue.Parse("video/mp4");
content.Add(videoContent);
HttpResponseMessage resp;
try {
resp = await client.PostAsync("SERVER_URL_GOES_HERE", content);
}
catch (Exception e)
{
return "EXCEPTION ERROR";
}
if (resp.StatusCode != HttpStatusCode.OK)
{
return resp.StatusCode.ToString();
}
var reponse = await resp.Content.ReadAsStringAsync();
return reponse;
}
Change accordingly.
Note: HttpClient is also using HttpWebRequest under the hood.
Also I don't think its a good idea to have the UI thread making the request. That makes no sense since you are blocking the interface and making the async theory useless.