Added support for Patch requests, added SetBody to ParameterCollection for directly setting the request body

CryptoExchange.Net/Authentication/AuthenticationProvider.cs

@@ -434,6 +434,20 @@ namespace CryptoExchange.Net.Authentication
             return DateTimeConverter.ConvertToMilliseconds(GetTimestamp(apiClient)).Value.ToString(CultureInfo.InvariantCulture);
         }
 
+        /// <summary>
+        /// Return the serialized request body
+        /// </summary>
+        /// <param name="serializer"></param>
+        /// <param name="parameters"></param>
+        /// <returns></returns>
+        protected string GetSerializedBody(IMessageSerializer serializer, IDictionary<string, object> parameters)
+        {
+            if (parameters.Count == 1 && parameters.ContainsKey(Constants.BodyPlaceHolderKey))
+                return serializer.Serialize(parameters[Constants.BodyPlaceHolderKey]);
+            else
+                return serializer.Serialize(parameters);
+        }
+
         /// <inheritdoc />
         public void Dispose()
         {

CryptoExchange.Net/Clients/RestApiClient.cs

@@ -75,7 +75,8 @@ namespace CryptoExchange.Net.Clients
             { HttpMethod.Get, HttpMethodParameterPosition.InUri },
             { HttpMethod.Post, HttpMethodParameterPosition.InBody },
             { HttpMethod.Delete, HttpMethodParameterPosition.InBody },
-            { HttpMethod.Put, HttpMethodParameterPosition.InBody }
+            { HttpMethod.Put, HttpMethodParameterPosition.InBody },
+            { new HttpMethod("Patch"), HttpMethodParameterPosition.InBody },
         };
 
         /// <inheritdoc />
@@ -804,7 +805,11 @@ namespace CryptoExchange.Net.Clients
             if (contentType == Constants.JsonContentHeader)
             {
                 // Write the parameters as json in the body
-                var stringData = CreateSerializer().Serialize(parameters);
+                string stringData;
+                if (parameters.Count == 1 && parameters.ContainsKey(Constants.BodyPlaceHolderKey))
+                    stringData = CreateSerializer().Serialize(parameters[Constants.BodyPlaceHolderKey]);
+                else
+                    stringData = CreateSerializer().Serialize(parameters);
                 request.SetContent(stringData, contentType);
             }
             else if (contentType == Constants.FormContentHeader)

CryptoExchange.Net/Objects/Constants.cs

@@ -13,5 +13,9 @@
         /// Form content type header
         /// </summary>
         public const string FormContentHeader = "application/x-www-form-urlencoded";
+        /// <summary>
+        /// Placeholder key for when request body should be set to the value of this KVP
+        /// </summary>
+        public const string BodyPlaceHolderKey = "_BODY_";
     }
 }

CryptoExchange.Net/Objects/ParameterCollection.cs

@@ -3,6 +3,7 @@ using CryptoExchange.Net.Converters.SystemTextJson;
 using System;
 using System.Collections.Generic;
 using System.Globalization;
+using System.Linq;
 
 namespace CryptoExchange.Net.Objects
 {
@@ -193,5 +194,18 @@ namespace CryptoExchange.Net.Objects
                 Add(key, int.Parse(stringVal));
             }
         }
+
+        /// <summary>
+        /// Set the request body. Can be used to specify a simple value or array as the body instead of an object
+        /// </summary>
+        /// <param name="body">Body to set</param>
+        /// <exception cref="InvalidOperationException"></exception>
+        public void SetBody(object body)
+        {
+            if (this.Any())
+                throw new InvalidOperationException("Can't set body when other parameters already specified");
+
+            Add(Constants.BodyPlaceHolderKey, body);
+        }
     }
 }

docs/index.html

@@ -82,16 +82,17 @@
           <ul class="nav flex-column">
             <li class="nav-item"><a class="nav-link" href="#idocs_installation">Installation</a></li>
             <li class="nav-item"><a class="nav-link" href="#idocs_di">Dependency Injection</a></li>
+            <li class="nav-item"><a class="nav-link" href="#idocs_general">General Client Usage</a></li>
             <li class="nav-item"><a class="nav-link" href="#idocs_rest">REST API Client</a></li>
             <li class="nav-item"><a class="nav-link" href="#idocs_socket">Websocket API Client</a></li>
-            <li class="nav-item"><a class="nav-link" href="#idocs_common">Common clients</a></li>
+            <li class="nav-item"><a class="nav-link" href="#idocs_common">Common Clients</a></li>
           </ul>
         </li>
         <li class="nav-item"><a class="nav-link" href="#idocs_options">Options & Authorization</a>
 		  <ul class="nav flex-column">
             <li class="nav-item"><a class="nav-link" href="#idocs_auth">Authorization</a></li>
-            <li class="nav-item"><a class="nav-link" href="#idocs_options_set">Setting options</a></li>
+            <li class="nav-item"><a class="nav-link" href="#idocs_options_set">Setting Options</a></li>
-            <li class="nav-item"><a class="nav-link" href="#idocs_options_def">Option definitions</a></li>
+            <li class="nav-item"><a class="nav-link" href="#idocs_options_def">Option Definitions</a></li>
           </ul>
         </li>
         <li class="nav-item"><a class="nav-link" href="#idocs_features">Additional Features</a>
@@ -812,6 +813,15 @@
         
 		<hr class="divider">
 		
+		<section id="idocs_general">
+          <h2>General client usage</h2>
+		  <p>All clients work with the same principles:</p>
+		  <ul>
+		    <li>Mandatory parameters are non-nullable while optional parameters are nullable and will have a default value of null.</li>
+		    <li>Any operation will return a form of <code>CallResult</code>. This result can and should be check for success. The clients will not throw exceptions.</li>
+		  </ul>
+		</section>
+		
         <!-- HTML Structure
 		============================ -->
         <section id="idocs_rest">