Added .NET Framework 471 as a target. .NET 5 is out

Author: alexeyzimarev

src/Directory.Build.props

@@ -1,7 +1,7 @@
 <Project>
     <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildProjectDirectory), 'RestSharp.sln'))\props\Common.props"/>
     <PropertyGroup>
-        <TargetFrameworks>netstandard2.0;net5.0;net6.0</TargetFrameworks>
+        <TargetFrameworks>netstandard2.0;net471;net6.0;net7.0</TargetFrameworks>
         <PackageIcon>restsharp.png</PackageIcon>
         <PackageLicenseExpression>Apache-2.0</PackageLicenseExpression>
         <PackageProjectUrl>https://restsharp.dev</PackageProjectUrl>

src/RestSharp.Serializers.CsvHelper/RestSharp.Serializers.CsvHelper.csproj

@@ -5,4 +5,7 @@
     <ItemGroup>
         <ProjectReference Include="..\RestSharp\RestSharp.csproj"/>
     </ItemGroup>
+    <ItemGroup>
+        <Using Remove="System.Net.Http"/>
+    </ItemGroup>
 </Project>

src/RestSharp.Serializers.NewtonsoftJson/RestSharp.Serializers.NewtonsoftJson.csproj

@@ -7,5 +7,6 @@
     </ItemGroup>
     <ItemGroup>
         <Using Include="Newtonsoft.Json"/>
+        <Using Remove="System.Net.Http"/>
     </ItemGroup>
 </Project>

src/RestSharp.Serializers.Xml/RestSharp.Serializers.Xml.csproj

@@ -5,4 +5,7 @@
     <ItemGroup>
         <ProjectReference Include="..\RestSharp\RestSharp.csproj"/>
     </ItemGroup>
+    <ItemGroup>
+        <Using Remove="System.Net.Http"/>
+    </ItemGroup>
 </Project>

src/RestSharp/Authenticators/OAuth/OAuth1Authenticator.cs

@@ -263,7 +263,7 @@ string GetAuthorizationHeader() {
             if (!Realm.IsEmpty())
                 oathParameters.Insert(0, $"realm=\"{OAuthTools.UrlEncodeRelaxed(Realm!)}\"");
 
-            return "OAuth " + string.Join(",", oathParameters);
+            return $"OAuth {string.Join(",", oathParameters)}";
         }
     }
 }

src/RestSharp/Extensions/StreamExtensions.cs

@@ -30,7 +30,7 @@ public static async Task<byte[]> ReadAsBytes(this Stream input, CancellationToke
         using var ms = new MemoryStream();
 
         int read;
-#if NETSTANDARD
+#if NETSTANDARD || NETFRAMEWORK
         while ((read = await input.ReadAsync(buffer, 0, buffer.Length, cancellationToken).ConfigureAwait(false)) > 0)
 #else
         while ((read = await input.ReadAsync(buffer, cancellationToken).ConfigureAwait(false)) > 0)

src/RestSharp/Properties/IsExternalInit.cs

@@ -1,4 +1,4 @@
-#if NETSTANDARD
+#if NETSTANDARD || NETFRAMEWORK
 using System.ComponentModel;
 
 // ReSharper disable once CheckNamespace

src/RestSharp/Response/ResponseHandling.cs

@@ -36,7 +36,7 @@ Encoding TryGetEncoding(string es) {
     }
 
     public static Task<Stream?> ReadResponse(this HttpResponseMessage response, CancellationToken cancellationToken) {
-#if NETSTANDARD
+#if NETSTANDARD || NETFRAMEWORK
         return response.Content.ReadAsStreamAsync();
 # else
         return response.Content.ReadAsStreamAsync(cancellationToken)!;

src/RestSharp/Response/RestResponse.cs

@@ -58,7 +58,7 @@ public static RestResponse<T> FromResponse(RestResponse response)
 /// <summary>
 /// Container for data sent back from API
 /// </summary>
-[DebuggerDisplay("{" + nameof(DebuggerDisplay) + "()}")]
+[DebuggerDisplay($"{{{nameof(DebuggerDisplay)}()}}")]
 public class RestResponse : RestResponseBase {
     internal static async Task<RestResponse> FromHttpResponse(
         HttpResponseMessage     httpResponse,
@@ -72,7 +72,7 @@ CancellationToken       cancellationToken
 
         async Task<RestResponse> GetDefaultResponse() {
             var readTask = request.ResponseWriter == null ? ReadResponse() : ReadAndConvertResponse();
-#if NETSTANDARD
+#if NETSTANDARD || NETFRAMEWORK
             using var stream = await readTask.ConfigureAwait(false);
 #else
             await using var stream = await readTask.ConfigureAwait(false);
@@ -105,7 +105,7 @@ async Task<RestResponse> GetDefaultResponse() {
             Exception? MaybeException()
                 => httpResponse.IsSuccessStatusCode
                     ? null
-#if NETSTANDARD
+#if NETSTANDARD || NETFRAMEWORK
                     : new HttpRequestException($"Request failed with status code {httpResponse.StatusCode}");
 #else
                     : new HttpRequestException($"Request failed with status code {httpResponse.StatusCode}", null, httpResponse.StatusCode);
@@ -114,7 +114,7 @@ async Task<RestResponse> GetDefaultResponse() {
             Task<Stream?> ReadResponse() => httpResponse.ReadResponse(cancellationToken);
 
             async Task<Stream?> ReadAndConvertResponse() {
-#if NETSTANDARD
+#if NETSTANDARD || NETFRAMEWORK
                 using var original = await ReadResponse().ConfigureAwait(false);
 #else
                 await using var original = await ReadResponse().ConfigureAwait(false);

src/RestSharp/RestClient.Async.cs

@@ -106,7 +106,7 @@ record InternalResponse(HttpResponseMessage? ResponseMessage, Uri Url, Exception
         if (response.ResponseMessage == null) return null;
 
         if (request.ResponseWriter != null) {
-#if NETSTANDARD
+#if NETSTANDARD || NETFRAMEWORK
             using var stream = await response.ResponseMessage.ReadResponse(cancellationToken).ConfigureAwait(false);
 #else
             await using var stream = await response.ResponseMessage.ReadResponse(cancellationToken).ConfigureAwait(false);
@@ -138,7 +138,7 @@ static HttpMethod AsHttpMethod(Method method)
             Method.Delete  => HttpMethod.Delete,
             Method.Head    => HttpMethod.Head,
             Method.Options => HttpMethod.Options,
-#if NETSTANDARD
+#if NETSTANDARD || NETFRAMEWORK
             Method.Patch => new HttpMethod("PATCH"),
 #else
             Method.Patch   => HttpMethod.Patch,