HttpClient does not exist in .net 4.0: what can I do? not found
httpclient c#
namespace for httpclient
package for httpclient
ssis system net http
system net reference
system net http unavailable
webclient c#

Ok i edited my code i dont get errors but the messageBox.Show return nothing empty box. Maybe i need to add something in the referrer string ? I didnt understand what is the referrer and what should i put there. And i have a key already im using it in my code. The key is a long string and im using it in my code i dont use with the referrer. Why it dosent translate the word "hi" ?

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Globalization;
using System.IO;
using System.Net;
using System.Web;
using System.Web.Script.Serialization;

namespace WindowsFormsApplication2
    public partial class Form1 : Form
        private JavaScriptSerializer _Serializer = new JavaScriptSerializer();

        public Form1()
            string f = TranslateText("hi", "English", "German", "", "");

        private void Form1_Load(object sender, EventArgs e)

        public string TranslateText(string inputText, string sourceLanguage, string destinationLanguage, string referrer, string apiKey)
                string requestUrl = string.Format(

                    HttpWebRequest http = (HttpWebRequest)HttpWebRequest.Create(requestUrl);
                    http.Referer = referrer;
                    HttpWebResponse response = (HttpWebResponse)http.GetResponse();
                    using (StreamReader sr = new StreamReader(response.GetResponseStream()))
                        string responseJson = sr.ReadToEnd();
                        var translation = this._Serializer.Deserialize<Milkshake.Integration.Google.GoogleAjaxResponse<Milkshake.Integration.Google.Translate.TranslationResponse>>(responseJson);

                        if (translation != null && translation.ResponseData != null && translation.ResponseData.ResponseStatus == HttpStatusCode.OK)
                            return translation.ResponseData.TranslatedText;
                            return String.Empty;
                    return String.Empty;

HttpClient Class (System.Net.Http), C# Copy. public class HttpClient : System.Net.Http.HttpMessageInvoker Properties of HttpClient should not be modified while there are outstanding requests,  I actually do know that Timeout.InfiniteTimespan does not exist in .NET 4.0. Noticed, there's also Timeout.Infinite which does exist in .NET 4.0 I know I could simply use an other overload, but I feel like something has to be more simple. I already tried using new TimeSpan (0, 0, -1) or new TimeSpan (-1) as dueTime.

I've used HttpClient in .NET 4.0 applications on numerous occasions. If you are familiar with NuGet, you can do an Install-Package Microsoft.Net.Http to add it to your project. See the link below for further details.

The type or namespace name 'Http' does not exist in the namespace , Hi Friends, I am having issues here, I am trying to use HttpClient to 'Http' does not exist in the namespace 'System.Net'. I have done all You will need to make sure you have referenced that namespace properly. NET Framework version, HttpClient is available in .NET 4.5 or 4.0 with the Microsoft.Net. The System.Net.Http namespace is designed to provide the following: HTTP client components that allow users to consume modern web services over HTTP. HTTP components that can be used by both clients and servers (HTTP headers and messages, for example).

Professional WCF 4: Windows Communication Foundation with .NET 4, Net.HttpStatusCode.OK ; On the contrary, the following line would return a status code 403 (Resource not found): WebOperationContext. control over communication between the server and client and do not have to worry about Listing 4-11 illustrates how the HttpClient class is used to send a GET request for a readout  The presence of SchUseStrongCrypto is good enough for any apps which are targeting .NET 4.0 - 4.6.2 to move to TLS 1.2. The explanation of SystemDefaultTlsVersions in the same documents, only mentions the cases, when 4.7 is installed on the system.

read this...

Portable HttpClient for .NET Framework and Windows Phone

see paragraph Using HttpClient on .NET Framework 4.0 or Windows Phone 7.5

System.Net.Http NuGet broken for .NET 4.7.2 · Issue #26131 · dotnet , Net.Http namespace is missing. I can't reference HttpClient . When I changed the redirect binding to (you can see that in solved my httpclient issue, but did not fix the system.runtime so I tried to do it for that nuget package too. @​jphellemons glad you found a workaround that fixed the issue. TLS 1.2 is not supported, but if you have .NET 4.5 (or above) installed on the system then you still can opt in for TLS 1.2 even if your application framework doesn’t support it. The only problem is that SecurityProtocolType in .NET 4.0 doesn’t have an entry for TLS1.2, so we’d have to use a numerical representation of this enum value:

Agreeing with TrueWill's comment on a separate answer, the best way I've seen to use system.web.http on a .NET 4 targeted project under current Visual Studio is Install-Package Microsoft.AspNet.WebApi.Client -Version 4.0.30506

Doesn't work with ASP.NET Web Application (.NET Framework , HttpClient Nevertheless makes this lib impossible to use. Recreation It would be good to not require the workaround found in #12 (comment)  If this registry setting does not exist, in .Net version 4.5.2 and below the value will be set to 'True', while in .Net 4.6.1 and above will be set to 'False'. Given that, if you just install .Net 4.6.1 and do not change strong cryptography Windows registry property,

Custom HTTP Clients for the Twilio C# Helper Library with .NET , When you take a closer look at the constructor for TwilioRestClient , you see that the httpClient parameter is actually of type Twilio.Http.HttpClient and not the  That resulting SampleLibrary.1.0.0.nupkg can now be properly used in both .NET Framework 4.6.1 or above projects and .NET Core projects targeting .NET Standard 1.6. tl;dr Your nuspec possibly has the correct dependencies for .NET Framework but it is not compiled against .NET Framework, so it will not work when the project is targeting .NET Framework.

HttpClient, This should/could be the case with System.Net.Http too? Or I have to copy it Can you check the Editor.log file for the C# compiler command line or namespace name `Http' does not exist in the namespace `System. Net.Http will be included in project by unity later? How do you decide what to include? This package includes HttpClient for sending requests over HTTP, as well as HttpRequestMessage and HttpResponseMessage for processing HTTP messages. This package is not supported in Visual Studio 2010, and is only required for projects targeting .NET Framework 4.5, Windows 8, or Windows Phone 8.1 when consuming a library that uses this package.

.NET 4 Wrox PDF Bundle: Professional ASP.NET 4, Professional C# 4, , NET 4, Professional C# 4, VB 2010 Programmer's Ref, WPF Programmer's Ref, NET Remoting, three channels are configured by default that can be used <​application> <channels> <channel ref="http client" displayName="http client (​delay So, it is not necessary to configure a channel in the client configuration file,  Angular 4.3 HttpClient (Accessing REST Web Services With Angular) “Property 'login' does not exist on type Because of a poor network connection or other circumstances which can not be

  • The title of this question is very clear, but the question itself is unclear. Admittedly it shows research effort, but that's all. There should be at least a sentence of context instead of letting the reader figuring out. I saw you edited your own question, you should again but make sure the end result is readable for a newcomer. Questions do have value on the long run, but participants have to make it possible.
  • dbasdeman i know this WebClient and httpwebrequest but i dont know how to use it in my code instead the httpclient...can you show me how to do it in my code ? Thanks.
  • System.Web.Http is for .net 4.5 i have 4.0 im using visual studio csharp pro 2010 and i dont have .net 4.5
  • I edited my code. No errors but the translation dosent work yet.
  • For those of us still on .NET 4.0, there is an implementation of HttpClient I've just learned about that you can install using NuGet at - See also
  • Hmm, I may have commented too quickly; another answer on this page from @cecilphillip says the same thing, but links to a different NuGet package. So... be sure to figure out which one to use!
  • yea... for mono you could use HttpWebRequest
  • It also says "This package is not supported in Visual Studio 2010, and is only required for projects targeting .NET Framework 4.5". Do you know what the difference is between this package, and ?
  • I know that HttpClinet you're linking to was pre RTM and isn't being worked on any more. I used HttpClient in a few .NET 4.0 apps. I'm really not sure why that verbiage is there
  • I've used Install-Package Microsoft.AspNet.WebApi.Client -Version 4.0.30506
  • For VS2010 the right version to use is
  • Using the link you provided, I was able to get my project to finally build! Thank you so much <3
  • @Smoore. Glad it helped.