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Asynchronous operation does not work even though I wrote it with async / await - C#

it's been a while that I try to write asynchronous code in C#, I did it and was sure it is asynchronous, recently I read I checked with postman the time that the function takes to finish when it's Asynchronous and when it's synchronous, and it seems like it takes the SAME time exactly, what I did wrong in my code?
Here is my code:
[HttpGet]
[Route("customerslist")]
public async Task<IHttpActionResult> getData()
{
string url1 = #"https://jsonplaceholder.typicode.com/photos";
string url2 = #"https://jsonplaceholder.typicode.com/comments";
string url3 = #"https://jsonplaceholder.typicode.com/todos";
Task<string> firstTask = myHttpCall(url1);
Task<string> secondTask = myHttpCall(url2);
Task<string> thirdTask = myHttpCall(url3);
await Task.WhenAll(firstTask, secondTask, thirdTask);
var result = firstTask.Result + secondTask.Result + thirdTask.Result;
return Ok(result);
}
private async Task<string> myHttpCall(string path)
{
string html = string.Empty;
string url = path;
// Simple http call to another URL to receive JSON lists.
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
request.AutomaticDecompression = DecompressionMethods.GZip;
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
using (Stream stream = response.GetResponseStream())
using (StreamReader reader = new StreamReader(stream))
{
html = reader.ReadToEnd();
}
return html;
}
I make HTTP request to another URL to get their JSON lists, anyone can help me please? I will be happy if anyone can tell me how to write it properly.

Your HTTP calls are synchronous. Use HttpClient in your myHttpCall method more or less like this:
private async Task<string> myHttpCall(string path)
{
using(HttpClient client = new HttpClient())
{
HttpResponseMessage response = await client.GetAsync(path);
return await response.Content.ReadAsStringAsync();
}
}
EDIT: To add automatic decompression pass following object to HttpClient constructor:
HttpClientHandler handler = new HttpClientHandler()
{
AutomaticDecompression = DecompressionMethods.GZip
};

C#: Error when HttpClient reponse

I am doing HTTP get request using HttpClient in C# console app . I am not getting expected response with one get request.
Get Request is like
http://example.com/xyz/SearchProduct?productNo=11210&1d6rstc9xc=5jyi27htzk
I am getting some vague response but when i do same get request with fiddler it is giving expected response.
How can I get expected response from httpClient.GetAsync(url)?
code is :-
var httpClient = new HttpClient();
var url = "http://example.com/xyz/SearchProduct?productNo=11210&1d6rstc9xc=5jyi27htzk";
HttpResponseMessage response1 = await httpClient.GetAsync(url);
if (response1.IsSuccessStatusCode)
{
HttpContent stream = response1.Content;
Task<string> data = stream.ReadAsStringAsync();
}

You should read as string that way:
string result = await stream.ReadAsStringAsync();
instead of that:
Task<string> data = stream.ReadAsStringAsync();
Here full code example and another example

This is a full method using async/await approach.
private static async Task<string> GetRequestContentAsString(string url)
{
var data = string.Empty;
using (var httpClient = new HttpClient())
{
var response = await httpClient.GetAsync(url);
if (response.IsSuccessStatusCode)
{
var stream = response.Content;
data = await stream.ReadAsStringAsync();
}
}
return data;
}
This method is called this way:
var content = await GetRequestContentAsString("http://www.bing.com");

Endless wait for async Web Response

i have the following problem, i try to wait for for an Async Web Response.
But it never finished.
public string getTermine(string trmId)
{
System.Threading.Tasks.Task<string> lisi = LoadTermine((HttpWebRequest)WebRequest.Create("http://" + curent.usrCH + apiKey + curent.phrase + apiTrmIDIS + trmId));//Request get String result like http://ajax.googleapis.com/ajax/services/search/web?v=1.0&start="+i+"&q=
lisi.Wait();
return lisi.Result;
}
private async System.Threading.Tasks.Taskstring>LoadTermine(HttpWebRequest myRequest)
{
//List<Termine> terminListe = new List<Termine>();
List<Appointment> Resu = null;
using (WebResponse response = await myRequest.GetResponseAsync())
{
using (System.IO.StreamReader reader = new System.IO.StreamReader(response.GetResponseStream()))
{
Resu = reader.ReadToEnd();
}
}
return Resu;
}
P.S. I cant use and synchronous request because this methods are an part of the Base code which is used by iOS, WinPhone and Android and i dont know why i cant get an synchronous WebResponse.

You are creating a deadlock by calling .Result on the task.
You could do something like this where the remoteUrl variabled is the url of your web service
private async System.Threading.Tasks.Task<string> LoadTermineAsync(HttpWebRequest myRequest)
{
using (var client = new HttpClient()) {
using (var request = new HttpRequestMessage(HttpMethod.Get, myRemoteUrl)) {
var response = await client.SendAsync(request).ConfigureAwait(false);
var result = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
return result;
}
}
}
For more info on Async/Await
And this evolve video is a little bit more advanced.

Bad Encoding when receiving response from HttpClient in UWP

I am making uwp(Universal Windows Platform) application and want to deserialize this xml: http://radioa24.info/ramowka.php to object, but I got instead for scpecial characters as ł, ó some strange letters and special ones like: \n and \r:
"Ä…"=>"ą"
"ć"=>"ć"
"Ä™"=>"ę"
For example instead of Poniedziałek i got PoniedziaÅ\u0082ek
My code:
var httpClient = new HttpClient();
var response = await httpClient.GetAsync(uri).AsTask();
response.EnsureSuccessStatusCode();
var result = await httpResponse.Content.ReadAsStringAsync();
I was trying to make some Encoding convertions but nothing worked out.
How to solve it because later I want to got my object?
var reader = new XmlSerializer(typeof(Sources.Schedule));
using (var tr = new MemoryStream(Encoding.UTF8.GetBytes(resultString)))
{
Schedule = (Sources.Schedule)reader.Deserialize(res);
}

Please can you try the code below, reading data as bytes solves your issue.
using (HttpClient client = new HttpClient())
{
Uri url = new Uri("http://radioa24.info/ramowka.php");
HttpRequestMessage httpRequest = new HttpRequestMessage(HttpMethod.Get, url);
Task<HttpResponseMessage> responseAsync = client.SendRequestAsync(httpRequest).AsTask();
responseAsync.Wait();
responseAsync.Result.EnsureSuccessStatusCode();
Task<IBuffer> asyncBuffer = responseAsync.Result.Content.ReadAsBufferAsync().AsTask();
asyncBuffer.Wait();
byte[] resultByteArray = asyncBuffer.Result.ToArray();
string responseString = Encoding.UTF8.GetString(resultByteArray, 0, resultByteArray.Length);
responseAsync.Result.Dispose();
}

As Jon Skeet notes in his answer this should be fixed on the server. If you check the server sends back the following Content-Type header:
Content-Type: text/xml
It should tell you the encoding (Content-Type: text/xml; charset=utf-8), that's why it should be a server fix.
But if you are sure that this is UTF-8 (it is, because the response xml contains <?xml version="1.0" encoding="UTF-8"?>), you can do this:
var httpClient = new HttpClient();
var response = await httpClient.GetBufferAsync(uri);
var bytes = response.ToArray();
var properEncodedString = Encoding.UTF8.GetString(bytes);

Here is my example that works fine with Polish words.
Method to get xml from page:
public async Task<string> GetXMl(string uri)
{
string result = null;
using (HttpClient httpClient = new HttpClient())
{
var response = await httpClient.GetAsync(uri);
result = await response.Content.ReadAsStringAsync();
}
return result;
}
Method to deserialize xml:
public void DeserializeXml(string xml)
{
var serializer = new XmlSerializer(typeof(ramowka));
var buffer = Encoding.UTF8.GetBytes(xml);
using (var stream = new MemoryStream(buffer))
{
var ramowka = (ramowka)serializer.Deserialize(stream);
}
}
Example how to use methods, for example in button click event:
private async void Button_Click(object sender, RoutedEventArgs e)
{
string xml = await GetXMl("http://radioa24.info/ramowka.php");
DeserializeXml(xml);
}
Also here you are converted by Visual Studio xml to C# classes
http://pastebin.com/aJ4B1aCF

C# HttpClient async POST request Task not returning a value

I'm executing an async POST request using a HttpClient in C#/Xamarin:
private async Task<string> ServicePostRequest (string url, string parameters)
{
string result = String.Empty;
using (var client = new HttpClient()) {
HttpContent content = new StringContent (parameters);
content.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue ("application/x-www-form-urlencoded");
client.Timeout = new TimeSpan (0, 0, 15);
using(var response = await client.PostAsync(url, content)){
using (var responseContent = response.Content) {
result = await responseContent.ReadAsStringAsync ();
Console.WriteLine (result);
return result;
}
}
}
}
When I execute the following code, the expected result (JSON) is being logged correctly in the terminal:
Task<string> result = ServicePostRequest("http://www.url.com", "parameters");
Now, I would like to get this result into a variable to be able to parse it. However, when I use the following code, no result is being logged at all and the application is frozen:
Task<string> result = ServicePostRequest("http://www.url.com", "parameters");
string myResult = result.Result;
Also when I use the result.Wait() method, the application doesn't respond at all.
Any help would be highly appreciated.

Since ServicePostRequest is an awaitable method, change this:
Task<string> result = ServicePostRequest("http://www.url.com", "parameters");
string myResult = result.Result;
To:
string result = await ServicePostRequest("http://www.url.com", "parameters");
Side Note: Make sure the calling method is an Asynchronous method.