Using interpolated strings for better code readability.

projects/Apigen/apigen/AmqpEntity.cs

@@ -82,11 +82,10 @@ public string DocumentationComment(string prefixSpaces, string docXpath) {
         public string DocumentationComment(string prefixSpaces, string docXpath, string tagname) {
             string docStr = GetString(docXpath, "").Trim();
             if (docStr.Length > 0) {
-                return (prefixSpaces + "/// <"+tagname+">\n" +
-                        GetString(docXpath, "") + "\n</"+tagname+">")
-                    .Replace("\n", "\n" + prefixSpaces + "/// ");
+                return $"{prefixSpaces}/// <{tagname}>\n{GetString(docXpath, "")}\n</{tagname}>"
+                    .Replace("\n", $"\n{prefixSpaces}/// ");
             } else {
-                return prefixSpaces + "// (no documentation)";
+                return $"{prefixSpaces}// (no documentation)";
             }
         }
     }

projects/Apigen/apigen/Apigen.cs

@@ -99,7 +99,7 @@ public static string GetString(XmlNode n0, string path)
             string s = GetString(n0, path, null);
             if (s == null)
             {
-                throw new Exception("Missing spec XML node: " + path);
+                throw new Exception($"Missing spec XML node: {path}");
             }
             return s;
         }
@@ -248,7 +248,7 @@ public void HandleOption(string opt)
             }
             else
             {
-                Console.Error.WriteLine("Unsupported command-line option: " + opt);
+                Console.Error.WriteLine($"Unsupported command-line option: {opt}");
                 Usage();
             }
         }
@@ -294,7 +294,7 @@ public void Generate()
 
         public void LoadSpec()
         {
-            Console.WriteLine("* Loading spec from '" + m_inputXmlFilename + "'");
+            Console.WriteLine($"* Loading spec from '{m_inputXmlFilename}'");
             m_spec = new XmlDocument();
 
             using (var stream = new FileStream(m_inputXmlFilename, FileMode.Open, FileAccess.Read))
@@ -358,12 +358,12 @@ public string MapDomain(string d)
 
         public string VersionToken()
         {
-            return "v" + m_majorVersion + "_" + m_minorVersion;
+            return $"v{m_majorVersion}_{m_minorVersion}";
         }
 
         public void GenerateOutput()
         {
-            Console.WriteLine("* Generating code into '" + m_outputFilename + "'");
+            Console.WriteLine($"* Generating code into '{m_outputFilename}'");
 
             string directory = Path.GetDirectoryName(m_outputFilename);
 
@@ -1069,11 +1069,11 @@ public void EmitContentHeaderFactory(MethodInfo method)
             EmitLine("    {");
             if (Attribute(method, typeof(AmqpUnsupportedAttribute)) != null)
             {
-                EmitLine(string.Format("      throw new UnsupportedMethodException(\"" + method.Name + "\");"));
+                EmitLine($"      throw new UnsupportedMethodException(\"{method.Name}\");");
             }
             else
             {
-                EmitLine("      return new " + MangleClass(contentClass) + "Properties();");
+                EmitLine($"      return new {MangleClass(contentClass)}Properties();");
             }
             EmitLine("    }");
         }
@@ -1101,7 +1101,7 @@ public void MaybeEmitModelMethod(MethodInfo method)
             {
                 EmitModelMethodPreamble(method);
                 EmitLine("    {");
-                EmitLine("      throw new UnsupportedMethodException(\"" + method.Name + "\");");
+                EmitLine($"      throw new UnsupportedMethodException(\"{method.Name}\");");
                 EmitLine("    }");
             }
             else
@@ -1198,7 +1198,7 @@ public void LookupAmqpMethod(MethodInfo method,
 
             if (amqpClass == null || amqpMethod == null)
             {
-                throw new Exception("Could not find AMQP class or method for IModel method " + method.Name);
+                throw new Exception($"Could not find AMQP class or method for IModel method {method.Name}");
             }
         }
 
@@ -1227,7 +1227,7 @@ public void EmitModelMethod(MethodInfo method)
                                                         : replyMapping.m_methodName);
                 if (amqpReplyMethod == null)
                 {
-                    throw new Exception("Could not find AMQP reply method for IModel method " + method.Name);
+                    throw new Exception($"Could not find AMQP reply method for IModel method {method.Name}");
                 }
             }
 
@@ -1269,7 +1269,7 @@ public void EmitModelMethod(MethodInfo method)
             string contentHeaderExpr =
                 contentHeaderParameter == null
                 ? "null"
-                : " (" + MangleClass(amqpClass.Name) + "Properties) " + contentHeaderParameter.Name;
+                : $" ({MangleClass(amqpClass.Name)}Properties) {contentHeaderParameter.Name}";
             string contentBodyExpr =
                 contentBodyParameter == null ? "null" : contentBodyParameter.Name;
 
@@ -1316,15 +1316,15 @@ public void EmitModelMethod(MethodInfo method)
 
             if (nowaitParameter != null)
             {
-                EmitLine("      if (" + nowaitParameter.Name + ") {");
-                EmitLine("        ModelSend(__req," + contentHeaderExpr + "," + contentBodyExpr + ");");
+                EmitLine($"      if ({nowaitParameter.Name}) {{");
+                EmitLine($"        ModelSend(__req,{contentHeaderExpr},{contentBodyExpr});");
                 if (method.ReturnType == typeof(void))
                 {
                     EmitLine("        return;");
                 }
                 else
                 {
-                    EmitLine("        return " + nowaitExpression + ";");
+                    EmitLine($"        return {nowaitExpression};");
                 }
                 EmitLine("      }");
             }
@@ -1334,7 +1334,7 @@ public void EmitModelMethod(MethodInfo method)
 
             if (amqpReplyMethod == null)
             {
-                EmitLine("      ModelSend(__req," + contentHeaderExpr + "," + contentBodyExpr + ");");
+                EmitLine($"      ModelSend(__req,{contentHeaderExpr},{contentBodyExpr});");
             }
             else
             {
@@ -1358,24 +1358,24 @@ public void EmitModelMethod(MethodInfo method)
                         string fieldPrefix = IsAmqpClass(method.ReturnType) ? "_" : "";
 
                         // No field mapping --> it's assumed to be a struct to fill in.
-                        EmitLine("      " + method.ReturnType + " __result = new " + method.ReturnType + "();");
+                        EmitLine($"      {method.ReturnType} __result = new {method.ReturnType}();");
                         foreach (FieldInfo fi in method.ReturnType.GetFields())
                         {
                             if (Attribute(fi, typeof(AmqpFieldMappingAttribute)) is AmqpFieldMappingAttribute returnFieldMapping)
                             {
-                                EmitLine("      __result." + fi.Name + " = __rep." + fieldPrefix + returnFieldMapping.m_fieldName + ";");
+                                EmitLine($"      __result.{fi.Name} = __rep.{fieldPrefix}{returnFieldMapping.m_fieldName};");
                             }
                             else
                             {
-                                EmitLine("      __result." + fi.Name + " = __rep." + fieldPrefix + fi.Name + ";");
+                                EmitLine($"      __result.{fi.Name} = __rep.{fieldPrefix}{fi.Name};");
                             }
                         }
                         EmitLine("      return __result;");
                     }
                     else
                     {
                         // Field mapping --> return just the field we're interested in.
-                        EmitLine("      return __rep._" + returnMapping.m_fieldName + ";");
+                        EmitLine($"      return __rep._{returnMapping.m_fieldName};");
                     }
                 }
             }

projects/RabbitMQ.Client/client/api/AmqpTcpEndpoint.cs

@@ -281,7 +281,7 @@ public override int GetHashCode()
         /// </remarks>
         public override string ToString()
         {
-            return "amqp://" + HostName + ":" + Port;
+            return $"amqp://{HostName}:{Port}";
         }
     }
 }

projects/RabbitMQ.Client/client/api/AmqpTimestamp.cs

@@ -79,7 +79,7 @@ public AmqpTimestamp(long unixTime) : this()
         /// </summary>
         public override string ToString()
         {
-            return "((time_t)" + UnixTime + ")";
+            return $"((time_t){UnixTime})";
         }
     }
 }

projects/RabbitMQ.Client/client/api/ConnectionFactory.cs

@@ -548,7 +548,7 @@ private void SetUri(Uri uri)
             }
             else
             {
-                throw new ArgumentException("Wrong scheme in AMQP URI: " + uri.Scheme);
+                throw new ArgumentException($"Wrong scheme in AMQP URI: {uri.Scheme}");
             }
             string host = uri.Host;
             if (!string.IsNullOrEmpty(host))
@@ -569,7 +569,7 @@ private void SetUri(Uri uri)
                 string[] userPass = userInfo.Split(':');
                 if (userPass.Length > 2)
                 {
-                    throw new ArgumentException("Bad user info in AMQP " + "URI: " + userInfo);
+                    throw new ArgumentException($"Bad user info in AMQP URI: {userInfo}");
                 }
                 UserName = UriDecode(userPass[0]);
                 if (userPass.Length == 2)
@@ -582,9 +582,7 @@ private void SetUri(Uri uri)
                that has at least the path segment "/". */
             if (uri.Segments.Length > 2)
             {
-                throw new ArgumentException("Multiple segments in " +
-                                            "path of AMQP URI: " +
-                                            string.Join(", ", uri.Segments));
+                throw new ArgumentException($"Multiple segments in path of AMQP URI: {string.Join(", ", uri.Segments)}");
             }
             if (uri.Segments.Length == 2)
             {

projects/RabbitMQ.Client/client/api/PlainMechanism.cs

@@ -46,7 +46,7 @@ public class PlainMechanism : IAuthMechanism
     {
         public byte[] handleChallenge(byte[] challenge, IConnectionFactory factory)
         {
-            return Encoding.UTF8.GetBytes("\0" + factory.UserName + "\0" + factory.Password);
+            return Encoding.UTF8.GetBytes($"\0{factory.UserName}\0{factory.Password}");
         }
     }
 }

projects/RabbitMQ.Client/client/api/PublicationAddress.cs

@@ -147,7 +147,7 @@ public static bool TryParse(string uriLikeString, out PublicationAddress result)
         /// </summary>
         public override string ToString()
         {
-            return ExchangeType + "://" + ExchangeName + "/" + RoutingKey;
+            return $"{ExchangeType}://{ExchangeName}/{RoutingKey}";
         }
     }
 }

projects/RabbitMQ.Client/client/api/ShutdownReportEntry.cs

@@ -66,8 +66,8 @@ public ShutdownReportEntry(string description, Exception exception)
 
         public override string ToString()
         {
-            string output = "Message: " + Description;
-            return (Exception != null) ? output + " Exception: " + Exception : output;
+            string description = $"Message: {Description}";
+            return (Exception != null) ? $"{description} Exception: {Exception}" : description;
         }
     }
 }

projects/RabbitMQ.Client/client/impl/AmqpVersion.cs

@@ -110,7 +110,7 @@ public override int GetHashCode()
         /// </remarks>
         public override string ToString()
         {
-            return Major + "-" + Minor;
+            return $"{Major}-{Minor}";
         }
     }
 }

projects/RabbitMQ.Client/client/impl/Connection.cs

@@ -260,8 +260,7 @@ public static IDictionary<string, object> DefaultClientProperties()
                 ["version"] = Encoding.UTF8.GetBytes(s_version),
                 ["platform"] = Encoding.UTF8.GetBytes(".NET"),
                 ["copyright"] = Encoding.UTF8.GetBytes("Copyright (c) 2007-2020 VMware, Inc."),
-                ["information"] = Encoding.UTF8.GetBytes("Licensed under the MPL.  " +
-                                                          "See https://www.rabbitmq.com/")
+                ["information"] = Encoding.UTF8.GetBytes("Licensed under the MPL. See https://www.rabbitmq.com/")
             };
             return table;
         }
@@ -335,8 +334,7 @@ public void Close(ShutdownEventArgs reason, bool abort, TimeSpan timeout)
                         }
                         else
                         {
-                            LogCloseError("Couldn't close connection cleanly. "
-                                          + "Socket closed unexpectedly", ioe);
+                            LogCloseError("Couldn't close connection cleanly. Socket closed unexpectedly", ioe);
                         }
                     }
                 }
@@ -378,14 +376,12 @@ public void ClosingLoop()
             {
                 if (_model0.CloseReason == null)
                 {
-                    LogCloseError("Connection didn't close cleanly. "
-                                  + "Socket closed unexpectedly", eose);
+                    LogCloseError("Connection didn't close cleanly. Socket closed unexpectedly", eose);
                 }
             }
             catch (IOException ioe)
             {
-                LogCloseError("Connection didn't close cleanly. "
-                              + "Socket closed unexpectedly", ioe);
+                LogCloseError("Connection didn't close cleanly. Socket closed unexpectedly", ioe);
             }
             catch (Exception e)
             {
@@ -447,7 +443,7 @@ public void HandleMainLoopException(ShutdownEventArgs reason)
             }
 
             OnShutdown();
-            LogCloseError("Unexpected connection closure: " + reason, new Exception(reason.ToString()));
+            LogCloseError($"Unexpected connection closure: {reason}", new Exception(reason.ToString()));
         }
 
         public bool HardProtocolExceptionHandler(HardProtocolException hpe)
@@ -470,8 +466,7 @@ public bool HardProtocolExceptionHandler(HardProtocolException hpe)
             }
             else
             {
-                LogCloseError("Hard Protocol Exception occured "
-                              + "while closing the connection", hpe);
+                LogCloseError("Hard Protocol Exception occured while closing the connection", hpe);
             }
 
             return false;
@@ -1117,8 +1112,7 @@ void StartAndTune()
                 IAuthMechanismFactory mechanismFactory = _factory.AuthMechanismFactory(mechanisms);
                 if (mechanismFactory == null)
                 {
-                    throw new IOException("No compatible authentication mechanism found - " +
-                                          "server offered [" + mechanismsString + "]");
+                    throw new IOException($"No compatible authentication mechanism found - server offered [{mechanismsString}]");
                 }
                 IAuthMechanism mechanism = mechanismFactory.GetInstance();
                 byte[] challenge = null;

projects/RabbitMQ.Client/client/impl/Frame.cs

@@ -276,7 +276,7 @@ internal static InboundFrame ReadFrom(Stream reader)
             if (frameEndMarker != Constants.FrameEnd)
             {
                 ArrayPool<byte>.Shared.Return(payloadBytes);
-                throw new MalformedFrameException("Bad frame end marker: " + frameEndMarker);
+                throw new MalformedFrameException($"Bad frame end marker: {frameEndMarker}");
             }
 
             return new InboundFrame((FrameType)type, channel, payload);

projects/RabbitMQ.Client/client/impl/ModelBase.cs

@@ -640,9 +640,7 @@ public virtual void HandleBasicDeliver(string consumerTag,
             {
                 if (DefaultConsumer == null)
                 {
-                    throw new InvalidOperationException("Unsolicited delivery -" +
-                                                        " see IModel.DefaultConsumer to handle this" +
-                                                        " case.");
+                    throw new InvalidOperationException("Unsolicited delivery - see IModel.DefaultConsumer to handle this case.");
                 }
                 else
                 {

projects/RabbitMQ.Client/client/impl/RecordedBinding.cs

@@ -93,8 +93,7 @@ public virtual void Recover()
 
         public override string ToString()
         {
-            return string.Format("{0}: source = '{1}', destination = '{2}', routingKey = '{3}', arguments = '{4}'",
-                GetType().Name, Source, Destination, RoutingKey, Arguments);
+            return $"{GetType().Name}: source = '{Source}', destination = '{Destination}', routingKey = '{RoutingKey}', arguments = '{Arguments}'";
         }
 
         public RecordedBinding WithArguments(IDictionary<string, object> value)

projects/RabbitMQ.Client/client/impl/RecordedExchange.cs

@@ -61,8 +61,7 @@ public void Recover()
 
         public override string ToString()
         {
-            return string.Format("{0}: name = '{1}', type = '{2}', durable = {3}, autoDelete = {4}, arguments = '{5}'",
-                GetType().Name, Name, Type, Durable, IsAutoDelete, Arguments);
+            return $"{GetType().Name}: name = '{Name}', type = '{Type}', durable = {Durable}, autoDelete = {IsAutoDelete}, arguments = '{Arguments}'";
         }
 
         public RecordedExchange WithArguments(IDictionary<string, object> value)

projects/RabbitMQ.Client/client/impl/RecordedQueue.cs

@@ -110,8 +110,7 @@ public RecordedQueue ServerNamed(bool value)
 
         public override string ToString()
         {
-            return string.Format("{0}: name = '{1}', durable = {2}, exlusive = {3}, autoDelete = {4}, arguments = '{5}'",
-                GetType().Name, Name, _durable, _exclusive, IsAutoDelete, _arguments);
+            return $"{GetType().Name}: name = '{Name}', durable = {_durable}, exlusive = {_exclusive}, autoDelete = {IsAutoDelete}, arguments = '{_arguments}'";
         }
     }
 }

projects/RabbitMQ.Client/client/impl/SessionBase.cs

@@ -127,7 +127,7 @@ public virtual void OnSessionShutdown(ShutdownEventArgs reason)
 
         public override string ToString()
         {
-            return GetType().Name + "#" + ChannelNumber + ":" + Connection;
+            return $"{GetType().Name}#{ChannelNumber}:{Connection}";
         }
 
         public void Close(ShutdownEventArgs reason)

projects/RabbitMQ.Client/client/impl/TcpClientAdapter.cs

@@ -24,7 +24,7 @@ public virtual async Task ConnectAsync(string host, int port)
             IPAddress ep = TcpClientAdapterHelper.GetMatchingHost(adds, _sock.AddressFamily);
             if (ep == default(IPAddress))
             {
-                throw new ArgumentException("No ip address could be resolved for " + host);
+                throw new ArgumentException($"No ip address could be resolved for {host}");
             }
 
 #if NET461

projects/RabbitMQ.Client/client/logging/RabbitMqExceptionDetail.cs

@@ -79,7 +79,7 @@ public RabbitMqExceptionDetail(IDictionary<string, object> ex)
 
         public override string ToString()
         {
-            return string.Format("Exception: {0}\r\n{1}\r\n\r\n{2}\r\nInnerException:\r\n{3}", Type, Message, StackTrace, InnerException);
+            return $"Exception: {Type}\r\n{Message}\r\n\r\n{StackTrace}\r\nInnerException:\r\n{InnerException}";
         }
     }
 }