Develop Reference

Xamarin.Android: How Can I Pass WebView Login Creds Into HttpWebRequest?

I am trying to pass login creds from a WebView into an HttpWebRequest but not having any luck getting an authenticated response. I am able to successfully make the request, but the response is acting like I haven't logged in. My app has 5 WebViews contained within Fragment s and I'm logged in on all of them. I've tried using the CookieSyncManager but it's deprecated and .Sync() didn't work. I've tried a lot of different ways of passing the cookies into the HttpRequest with no success and many hours spent.
One would think this is a simple request; user has logged in within the app; they should be authenticated for all requests. Here's the closest that I've gotten, but the response string is still not the same as through my authenticated WebView :
This attempt parses each Cookie into a string and adds it
public string _cookieString { get; set; }
private class ExtWebViewClient : WebViewClient
{
TheFragment5 _fm5 = new TheFragment5();
public override void OnPageFinished(WebView view, string url)
{
var cookieHeader = Android.Webkit.CookieManager.Instance.GetCookie(url);
var cookiePairs = cookieHeader.Split('&');
_fm5._cookieString = "";
foreach (var cookiePair in cookiePairs)
{
var cookiePieces = cookiePair.Split('=');
if (cookiePieces[0].Contains(":"))
cookiePieces[0] = cookiePieces[0].Substring(0, cookiePieces[0].IndexOf(":"));
cookies.Add(new Cookie
{
Name = cookiePieces[0],
Value = cookiePieces[1]
});
}
foreach (Cookie c in cookies)
{
if (_fm5._cookieString == "")
{
_fm5._cookieString = c.ToString();
}
else
{
_fm5._cookieString += c.ToString();
}
}
}
}
I've also tried just doing:
_fm5._cookieString = cookieHeader.ToString();
but neither of those attempts is working when I add the cookie string into my HttpRequest :
public async void GetNotificationText(string url)
{
//var _cmhc = _cookieMan.HasCookies;
await Task.Run(() =>
{
_notificationHttpRequestInProgress = true;
try
{
var _ctxxx = Android.App.Application.Context;
//URL _url2 = new URL("https://bitchute.com/notifications/");
//HttpURLConnection conn = (HttpURLConnection)_url2.OpenConnection();
//conn.ReadTimeout = 10000 /* milliseconds */;
//conn.ConnectTimeout = 15000 /* milliseconds */;
////conn.SetRequestProperty("Cookie", cookies);
//conn.Connect();
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
Uri uri = new Uri(url);
var _req = request;
var _uriii = uri;
var _cookiesss = _fm5._cookieString;
_cookieCon.SetCookies(uri, _cookiesss);
request.CookieContainer = _cookieCon;
//request.CookieContainer.SetCookies(uri, _cookiesss);
request.AutomaticDecompression = DecompressionMethods.GZip;
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
using (Stream stream = response.GetResponseStream())
using (StreamReader reader = new StreamReader(stream))
{
_notificationRawText = reader.ReadToEnd();
Console.WriteLine(_notificationRawText);
_rawNoteText = _notificationRawText;
}
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
_notificationHttpRequestInProgress = false;
});
}
This returns, but not the authenticated webtext request; I get the same response any user would get on a browser having never logged in. If I were to browse out to this same url on any WebView in my app, I'd get a completely different response.
You will also notice some commented out code that was another failed attempt at adding the cookies into a connection. I had also tried using HttpURLConnection.SetRequestProperty("Cookie", cookies);
where cookies was a CookieCollection and that didn't work either. The code is mostly commented out and layered because I've been trying this for days.
Does anyone know how I can pass WebView cookies into an HttpRequest using Xamarin.Android?
I am putting this code below in Fragment5 of my app; you can see and compile the full context here:
https://github.com/hexag0d/BitChute_Mobile_Android_BottomNav/blob/NotificationAdder/Fragments/TheFragment5.cs

I'm not sure exactly why the above example didn't work; maybe if you're better at .NET than I am, you could figure it out. However, I was able to successfully pass WebView creds into an HttpClient by following these steps, which are returning an authenticated response. This may not be the most elegant way of doing it, but you can always refine my answer, or post a better one.
What I had to do was set the HttpClient.DefaultRequestHeaders using the .Add() method like this: _client.DefaultRequestHeaders.Add("Cookie", TheFragment5._cookieHeader);
I got the CookieHeader (which is just a string btw) like this:
//instantiate a string that will house our cookie header
public static string _cookieHeader;
//you might want to make it private to prevent abuse
//but this example is just for demonstration
//the thing is we need a string to house our headers in scope of both the WebView and the HttpClient
//extend the WebViewClient
private class ExtWebViewClient : WebViewClient
{
public override void OnPageFinished(WebView view, string url)
{
//I get the cookies when the page finishes loading because
//then we know the cookie has our login cred header
//also, most of the previous examples got the cookies OnPageFinished
TheFragment5._cookieHeader = Android.Webkit.CookieManager.Instance.GetCookie(url);
}
}
Then we need another method for the HttpClient and HttpClientHandler ... mine scans a webpage for notification text.
public async void GetNotificationText(string url)
{
await Task.Run(() =>
{
/* this line is pretty important,
we need to instantiate an HttpClientHandler
then set it's UseCookies property to false
so that it doesn't override our cookies
*/
HttpClientHandler handler = new HttpClientHandler() { UseCookies = false };
try
{
Uri _notificationURI = new Uri("https://bitchute.com/notifications/");
//instantiate HttpClient using the handler
using (HttpClient _client = new HttpClient(handler))
{
//this line is where the magic happens;
//we set the DefaultRequestHeaders with the cookieheader we got from WebViewClient.OnPageFinished
_client.DefaultRequestHeaders.Add("Cookie", TheFragment5._cookieHeader);
//do a GetAsync request with our cookied up client
var getRequest = _client.GetAsync("https://bitchute.com/notifications/").Result;
//resultContent is the authenticated html string response from the server, ready to be parsed =]
var resultContent = getRequest.Content.ReadAsStringAsync().Result;
/*
I was writing to console to check the
response.. for me, I am now getting
the authenticated notification html
page
*/
Console.WriteLine(resultContent);
}
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
}
}
Hope this helps you, posting for future reference, especially for people using Xamarin.Android.

How to Send/Read Image From HttpResponseMessage [duplicate]

My HttpClient sends the image with PostAsync.
I am not really sure what to do now since this is my first REST Api and I can't really adapt the things I sorted out in other posts yet.
Hopefully you guys can help me out and can give me a direction.
public async Task SendImage(string fullFileName, string fileName)
{
var client = new HttpClient();
client.BaseAddress = new Uri("http://x.x.x.x");
var content = new StringContent(fullFileName, Encoding.UTF8, "image/jpg");
HttpResponseMessage response = await client.PostAsync($"/values/file/{fileName}", content);
}
I have several questions about the POST function.
First of all I can successfully access it with PostMan and the fileName is correct.
How do I read the image data and write it to a file?
[HttpPost("file/{fileName}")]
public void Upload(string fileName)
{
Debug.Write(fileName);
}
EDIT:
I setup my environment and I can now send a post via the internet to my published Web Api.
On my app just nothing happens.
For now I just tried to get something of a message to work on but I dont getting one.
[HttpPost("file/{fileName}")]
public HttpResponseMessage Upload(UploadedFile fileName)
{
Debug.Write(fileName);
if (!ModelState.IsValid)
{
}
if (fileName == null)
{
}
string destinationPath = Path.Combine(#"C:\", fileName.FileFullName);
System.IO.File.WriteAllBytes(destinationPath, fileName.Data);
HttpResponseMessage rm = new HttpResponseMessage();
rm.StatusCode = HttpStatusCode.OK;
return rm;
}

1.Your controller should look like this:
//For .net core 2.1
[HttpPost]
public IActionResult Index(List<IFormFile> files)
{
//Do something with the files here.
return Ok();
}
//For previous versions
[HttpPost]
public IActionResult Index()
{
var files = Request.Form.Files;
//Do something with the files here.
return Ok();
}
2.To upload a file you can also use Multipart content:
public async Task UploadImageAsync(Stream image, string fileName)
{
HttpContent fileStreamContent = new StreamContent(image);
fileStreamContent.Headers.ContentDisposition = new System.Net.Http.Headers.ContentDispositionHeaderValue("form-data") { Name = "file", FileName = fileName };
fileStreamContent.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/octet-stream");
using (var client = new HttpClient())
using (var formData = new MultipartFormDataContent())
{
formData.Add(fileStreamContent);
var response = await client.PostAsync(url, formData);
return response.IsSuccessStatusCode;
}
}
3.If you are uploading large files you should consider streaming the files instead, you can read about it here

You're going fine until you're trying to retrieve the image data, I'm afraid.
According to your question:
How do I read the image data and write it to a file?
All you want to do is getting the file's data and its file name and sending it to your service.
I would personally create an UploadedFile class on both sides (client and service side), having the file's name and its data, so:
public class UploadedFile
{
public string FileFullName { get; set; }
public byte[] Data { get; set; }
public UploadedFile(string filePath)
{
FileFullName = Path.GetFileName(Normalize(filePath));
Data = File.ReadAllBytes(filePath);
}
private string Normalize(string input)
{
return new string(input
.Normalize(System.Text.NormalizationForm.FormD)
.Replace(" ", string.Empty)
.ToCharArray()
.Where(c => CharUnicodeInfo.GetUnicodeCategory(c) != UnicodeCategory.NonSpacingMark)
.ToArray());
}
}
Then you will need, for example, the NewtonSoft's JsonConvert in order to serialize the object and send it through.
So now you would be able to send your data async:
public async Task SendDataAsync(string fullFilePath)
{
if (!File.Exists(fullFilePath))
throw new FileNotFoundException();
var data = JsonConvert.SerializeObject(new UploadedFile(fullFilePath));
using (var client = new WebClient())
{
client.Headers.Add(HttpRequestHeader.ContentType, "application/json");
await client.UploadStringTaskAsync(new Uri("http://localhost:64204/api/upload/"), "POST", data);
}
}
Now, make sure you correctly handle the request on the server side. If for whatever reason the parameters doesn't match it won't enter into the method (remember having the same model/class - UploadedFile on the service as well).
On the service, just change the arguments of your method and perform something "like this":
[HttpPost]
public HttpResponseMessage Upload(UploadedFile file)
{
if (!ModelState.IsValid)
...
if (file == null)
...
string destinationPath = Path.Combine(_whateverPath, file.FileFullName);
File.WriteAllBytes(destinationPath, file.Data);
}
Hope it helped you having an idea about what to do and what you're actually doing wrong. I've exposed something similar based in my experience.
EDIT: I've actually uploaded an example with both sides working: a simple .NET Core console app which retrieves a file and sends it through POST and a basic WebAPI2 service with a simple controller to retrieve the data. Both ready to go and tested working! Download it here.
Enjoy.

Send image with HttpClient to POST WebApi and consume the data

My HttpClient sends the image with PostAsync.
I am not really sure what to do now since this is my first REST Api and I can't really adapt the things I sorted out in other posts yet.
Hopefully you guys can help me out and can give me a direction.
public async Task SendImage(string fullFileName, string fileName)
{
var client = new HttpClient();
client.BaseAddress = new Uri("http://x.x.x.x");
var content = new StringContent(fullFileName, Encoding.UTF8, "image/jpg");
HttpResponseMessage response = await client.PostAsync($"/values/file/{fileName}", content);
}
I have several questions about the POST function.
First of all I can successfully access it with PostMan and the fileName is correct.
How do I read the image data and write it to a file?
[HttpPost("file/{fileName}")]
public void Upload(string fileName)
{
Debug.Write(fileName);
}
EDIT:
I setup my environment and I can now send a post via the internet to my published Web Api.
On my app just nothing happens.
For now I just tried to get something of a message to work on but I dont getting one.
[HttpPost("file/{fileName}")]
public HttpResponseMessage Upload(UploadedFile fileName)
{
Debug.Write(fileName);
if (!ModelState.IsValid)
{
}
if (fileName == null)
{
}
string destinationPath = Path.Combine(#"C:\", fileName.FileFullName);
System.IO.File.WriteAllBytes(destinationPath, fileName.Data);
HttpResponseMessage rm = new HttpResponseMessage();
rm.StatusCode = HttpStatusCode.OK;
return rm;
}

1.Your controller should look like this:
//For .net core 2.1
[HttpPost]
public IActionResult Index(List<IFormFile> files)
{
//Do something with the files here.
return Ok();
}
//For previous versions
[HttpPost]
public IActionResult Index()
{
var files = Request.Form.Files;
//Do something with the files here.
return Ok();
}
2.To upload a file you can also use Multipart content:
public async Task UploadImageAsync(Stream image, string fileName)
{
HttpContent fileStreamContent = new StreamContent(image);
fileStreamContent.Headers.ContentDisposition = new System.Net.Http.Headers.ContentDispositionHeaderValue("form-data") { Name = "file", FileName = fileName };
fileStreamContent.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/octet-stream");
using (var client = new HttpClient())
using (var formData = new MultipartFormDataContent())
{
formData.Add(fileStreamContent);
var response = await client.PostAsync(url, formData);
return response.IsSuccessStatusCode;
}
}
3.If you are uploading large files you should consider streaming the files instead, you can read about it here

You're going fine until you're trying to retrieve the image data, I'm afraid.
According to your question:
How do I read the image data and write it to a file?
All you want to do is getting the file's data and its file name and sending it to your service.
I would personally create an UploadedFile class on both sides (client and service side), having the file's name and its data, so:
public class UploadedFile
{
public string FileFullName { get; set; }
public byte[] Data { get; set; }
public UploadedFile(string filePath)
{
FileFullName = Path.GetFileName(Normalize(filePath));
Data = File.ReadAllBytes(filePath);
}
private string Normalize(string input)
{
return new string(input
.Normalize(System.Text.NormalizationForm.FormD)
.Replace(" ", string.Empty)
.ToCharArray()
.Where(c => CharUnicodeInfo.GetUnicodeCategory(c) != UnicodeCategory.NonSpacingMark)
.ToArray());
}
}
Then you will need, for example, the NewtonSoft's JsonConvert in order to serialize the object and send it through.
So now you would be able to send your data async:
public async Task SendDataAsync(string fullFilePath)
{
if (!File.Exists(fullFilePath))
throw new FileNotFoundException();
var data = JsonConvert.SerializeObject(new UploadedFile(fullFilePath));
using (var client = new WebClient())
{
client.Headers.Add(HttpRequestHeader.ContentType, "application/json");
await client.UploadStringTaskAsync(new Uri("http://localhost:64204/api/upload/"), "POST", data);
}
}
Now, make sure you correctly handle the request on the server side. If for whatever reason the parameters doesn't match it won't enter into the method (remember having the same model/class - UploadedFile on the service as well).
On the service, just change the arguments of your method and perform something "like this":
[HttpPost]
public HttpResponseMessage Upload(UploadedFile file)
{
if (!ModelState.IsValid)
...
if (file == null)
...
string destinationPath = Path.Combine(_whateverPath, file.FileFullName);
File.WriteAllBytes(destinationPath, file.Data);
}
Hope it helped you having an idea about what to do and what you're actually doing wrong. I've exposed something similar based in my experience.
EDIT: I've actually uploaded an example with both sides working: a simple .NET Core console app which retrieves a file and sends it through POST and a basic WebAPI2 service with a simple controller to retrieve the data. Both ready to go and tested working! Download it here.
Enjoy.

Working cefsharp POST example

Having a difficult time getting an HTTP POST request/response using cefsharp / ChromiumWebBrowser. I'm unable to find a working example on Stackoverflow, nor in the documentation. Looking to see if anyone has a full example? I'm stuck on if it can be done with a Navigate function (as show in one example), or needs to be a done with a handler / schema.
I'm trying a basic POST to a PHP script. If the data1/data2 match the input, it's return json status:success, otherwise failure. I see in the devtools that the html body comes back with json success, but this code returns or nothing at all. I've tried too different ways to get the response data. I want to grab the JSON response for the C# code to review. Surely there should be an easy way to accomplish this? I want to send an HTTP request and then get the body (json) to parse. If this needs the schema/handler, I cannot find a full example of using this.
namespace BrowserTest
{
public partial class MainForm : Form
{
ChromiumWebBrowser browser = null;
public Loader()
{
browser = new ChromiumWebBrowser("http://localhost/test/"); // Initialize to this page
pBrowserLogin.Controls.Add(browser);
}
private void btnTest_Click(object sender, EventArgs e)
{
byte[] request = Encoding.ASCII.GetBytes("data1=" + txtData1.Text + "&data2=" + txtData2.Text);
PostTest.Navigate(browser, "http://localhost/test/posttest.php", request, "application/x-www-form-urlencoded");
}
}
public static class PostTest
{
public static void Navigate(this IWebBrowser browser, string url, byte[] postDataBytes, string contentType)
{
IFrame frame = browser.GetMainFrame();
IRequest request = frame.CreateRequest();
request.Url = url;
request.Method = "POST";
request.InitializePostData();
var element = request.PostData.CreatePostDataElement();
element.Bytes = postDataBytes;
request.PostData.AddElement(element);
NameValueCollection headers = new NameValueCollection();
headers.Add("Content-Type", contentType);
request.Headers = headers;
frame.LoadRequest(request);
frame.GetTextAsync().ContinueWith(taskHtml =>
{
var html = taskHtml.Result;
System.Windows.Forms.MessageBox.Show(html);
});
string script = string.Format("document.documentElement.outerHTML;");
frame.EvaluateScriptAsync(script).ContinueWith(x =>
{
var response = x.Result;
if (response.Success && response.Result != null)
{
var fullhtml = response.Result;
System.Windows.Forms.MessageBox.Show(fullhtml.ToString());
}
});
}
}
}

Consuming WEB API using HttpClient in c# console application

I have created a web API in visual studio 2015 using a MySQL database. The API is working perfect.
So I decided to make a console client application in which I can consume my web-service (web API). The client code is based on HttpClient, and in the API I have used HttpResponse. Now when I run my console application code, I get nothing. Below is my code:
Class
class meters_info_dev
{
public int id { get; set; }
public string meter_msn { get; set; }
public string meter_kwh { get; set; }
}
This class is same as in my web API model class:
Model in web API
namespace WebServiceMySQL.Models
{
using System;
using System.Collections.Generic;
public partial class meters_info_dev
{
public int id { get; set; }
public string meter_msn { get; set; }
public string meter_kwh { get; set; }
}
Console application code
static HttpClient client = new HttpClient();
static void ShowAllProducts(meters_info_dev mi)
{
Console.WriteLine($"Meter Serial Number:{mi.meter_msn}\t Meter_kwh: {mi.meter_kwh}", "\n");
}
static async Task<List<meters_info_dev>> GetAllRecordsAsync(string path)
{
List<meters_info_dev> mID = new List<meters_info_dev>();
HttpResponseMessage response = await client.GetAsync(path);
if (response.IsSuccessStatusCode)
{
mID = await response.Content.ReadAsAsync<List<meters_info_dev>>();
}
else
{
Console.WriteLine("No Record Found");
}
return mID;
}
static void Main()
{
RunAsync().Wait();
}
static async Task RunAsync()
{
client.BaseAddress = new Uri("http://localhost:2813/");
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
var m = await GetAllRecordsAsync("api/metersinfo/");
foreach(var b in m)
{
ShowAllProducts(b);
}
}
In my API I have 3 GET methods under a single controller, so I have created different routes for them. Also the URL for them is different.
http://localhost:2813/api/metersinfo/ will return all records
While debugging the code, I found that List<meters_info_dev> mID = new List<meters_info_dev>(); is empty:
While the response is 302 Found, the URL is also correct:
Update 1
After a suggestion I have done the following:
using (var client = new HttpClient())
{
List<meters_info_dev> mID = new List<meters_info_dev>();
HttpResponseMessage response = await client.GetAsync(path);
if (response.IsSuccessStatusCode)
{
mID = await response.Content.ReadAsAsync<List<meters_info_dev>>();
}
else
{
Console.WriteLine("No Record Found");
}
return mID;
}
When I run the application, I get the exception "An invalid request URI was provided. The request URI must either be an absolute URI or BaseAddress must be set."
Update 2
I have added a new piece of code:
using (var cl = new HttpClient())
{
var res = await cl.GetAsync("http://localhost:2813/api/metersinfo");
var resp = await res.Content.ReadAsStringAsync();
}
And in the response I am getting all the records:
I don't know why it's not working with the other logic and what the problem is. I have also read the questions Httpclient consume web api via console app C# and Consuming Api in Console Application.
Any help would be highly appreciated.

The code needs quite a bit of work.
The line you highlighted will always be empty because that's where you initialise the variable. What you want is run thorugh the code until you get the result back form the call.
First, make sure your api actually works, you can call the GET method you want in the browser and you see results.
using (var client = new HttpClient())
{
var result = await client.GetAsync("bla");
return await result.Content.ReadAsStringAsync();
}
that's an example of course, so replace that with your particular data and methods.
now, when you check the results just because your response.IsSuccessStatusCode is false that doesn't mean there are no records. What it means is that the call failed completely. Success result with an empty list is not the same thing as complete failure.
If you want to see what you get back you can alter your code a little bit:
if(response.IsSuccessStatusCode)
{
var responseData = await response.Content.ReadAsStringAsync();
//more stuff
}
put a breakpoint on this line and see what you actually get back, then you worry about casting the result to your list of objects. Just make sure you get back the same thing you get when you test the call in the browser.
<------------------------------->
More details after edit.
Why don't you simplify your code a little bit.
for example just set the URL of the request in one go :
using (var client = new HttpClient())
{
var result = await client.GetAsync("http://localhost:2813/api/metersinfo");
var response = await result.Content.ReadAsStringAsync();
//set debug point here and check to see if you get the correct data in the response object
}
Your first order of the day is to see if you can hit the url and get the data.
You can worry about the base address once you get a correct response. Start simple and work your way up from there, once you have a working sample.
<----------------- new edit ---------------->
Ok, now that you are getting a response back, you can serialise the string back to the list of objects using something like Newtonsoft.Json. This is a NuGet package, you might either have it already installed, if not just add it.
Add a using statement at the top of the file.
using Newtonsoft.Json;
then your code becomes something like :
using (var client = new HttpClient())
{
var result = await client.GetAsync("bla");
var response = await result.Content.ReadAsStringAsync();
var mID = JsonConvert.DeserializeObject<List<meters_info_dev>>(response);
}
At this point you should have your list of objects and you can do whatever else you need.