如何在WCF REST端点中将JSON响应转为CamelCase格式？

没问题，在现有WCF REST服务里完全能实现PascalCase转CamelCase的JSON输出，不用额外新建Web API或MVC项目，给你两种实用方案：

先明确下需求：你的WCF响应类用的是PascalCase命名（比如Packages、Messages），但希望返回的JSON字段是camelCase（比如packages、messages），下面两种方案都能满足：

方案一：手动指定字段名（简单直接，适合小体量模型） #

WCF默认的DataContractJsonSerializer支持通过DataMember特性的Name参数，直接指定JSON输出的字段名。你只需要给响应类及其子类的每个属性加上这个配置：

using System.Runtime.Serialization;

[DataContract]
public class PackageConfigResponse
{
    [DataMember(Name = "packages")]
    public List<Package> Packages { get; set; }

    [DataMember(Name = "messages")]
    public MessageInfo Messages { get; set; }
}

// 子类型也要做同样处理
[DataContract]
public class Package
{
    [DataMember(Name = "packageId")]
    public int PackageId { get; set; }
    
    // 其他属性按此格式添加DataMember
}

[DataContract]
public class MessageInfo
{
    [DataMember(Name = "messageType")]
    public string MessageType { get; set; }
    
    // 其他属性按此格式添加DataMember
}

这种方法优点是上手快，不需要额外配置类；缺点是如果模型类多、属性多，需要逐个修改，比较繁琐。

方案二：自定义序列化行为（自动转换，适合大量模型） #

如果你的模型类数量多，不想手动改每个属性，可以自定义WCF的序列化行为，自动把PascalCase转为CamelCase。这里推荐用你熟悉的Newtonsoft.Json（Json.NET）来替换默认序列化器，配置起来更灵活：

步骤1：实现Newtonsoft.Json调度格式化器 #

创建一个格式化器，用Json.NET的CamelCasePropertyNamesContractResolver自动处理命名转换：

using Newtonsoft.Json;
using Newtonsoft.Json.Serialization;
using System.ServiceModel.Channels;
using System.ServiceModel.Dispatcher;
using System.IO;
using System.Text;

public class NewtonsoftJsonDispatchFormatter : IDispatchMessageFormatter
{
    private readonly OperationDescription _operation;
    private readonly JsonSerializerSettings _jsonSettings;

    public NewtonsoftJsonDispatchFormatter(OperationDescription operation)
    {
        _operation = operation;
        // 配置驼峰命名解析器
        _jsonSettings = new JsonSerializerSettings
        {
            ContractResolver = new CamelCasePropertyNamesContractResolver(),
            Formatting = Formatting.Indented // 可选，格式化JSON输出更易读
        };
    }

    // 处理请求反序列化（如果需要支持camelCase格式的请求，可保留此逻辑）
    public void DeserializeRequest(Message message, object[] parameters)
    {
        var bodyReader = message.GetReaderAtBodyContents();
        bodyReader.ReadStartElement("Binary");
        var jsonBytes = bodyReader.ReadContentAsBase64();
        var json = Encoding.UTF8.GetString(jsonBytes);
        var paramType = _operation.Messages[0].Body.Parts[0].Type;
        parameters[0] = JsonConvert.DeserializeObject(json, paramType, _jsonSettings);
    }

    // 处理响应序列化，核心是用Json.NET生成camelCase的JSON
    public Message SerializeReply(MessageVersion messageVersion, object[] parameters, object result)
    {
        var json = JsonConvert.SerializeObject(result, _jsonSettings);
        var bytes = Encoding.UTF8.GetBytes(json);
        var stream = new MemoryStream(bytes);
        
        var replyMessage = Message.CreateMessage(messageVersion, null, new RawBodyWriter(stream));
        replyMessage.Properties.Add(WebBodyFormatMessageProperty.Name, new WebBodyFormatMessageProperty(WebContentFormat.Json));
        
        var httpResponse = replyMessage.Properties[HttpResponseMessageProperty.Name] as HttpResponseMessageProperty ?? new HttpResponseMessageProperty();
        httpResponse.Headers[HttpResponseHeader.ContentType] = "application/json; charset=utf-8";
        replyMessage.Properties[HttpResponseMessageProperty.Name] = httpResponse;
        
        return replyMessage;
    }

    // 辅助类：处理原始流写入
    private class RawBodyWriter : BodyWriter
    {
        private readonly Stream _stream;
        public RawBodyWriter(Stream stream) : base(true) => _stream = stream;

        protected override void OnWriteBodyContents(XmlDictionaryWriter writer)
        {
            writer.WriteStartElement("Binary");
            var buffer = new byte[1024];
            int bytesRead;
            while ((bytesRead = _stream.Read(buffer, 0, buffer.Length)) > 0)
            {
                writer.WriteBase64(buffer, 0, bytesRead);
            }
            writer.WriteEndElement();
        }
    }
}

步骤2：创建自定义WCF行为 #

让WCF使用我们刚才的格式化器：

using System.ServiceModel.Description;
using System.ServiceModel.Dispatcher;

public class NewtonsoftJsonBehavior : WebHttpBehavior
{
    protected override IDispatchMessageFormatter GetRequestDispatchFormatter(OperationDescription operationDescription, ServiceEndpoint endpoint)
    {
        return new NewtonsoftJsonDispatchFormatter(operationDescription);
    }

    protected override IDispatchMessageFormatter GetReplyDispatchFormatter(OperationDescription operationDescription, ServiceEndpoint endpoint)
    {
        return new NewtonsoftJsonDispatchFormatter(operationDescription);
    }
}

步骤3：注册行为（二选一） #

方式A：代码注册行为

在服务启动时添加这个行为：

var serviceHost = new ServiceHost(typeof(FormsConfigTool));
var endpoint = serviceHost.AddServiceEndpoint(typeof(IFormsConfigTool), new WebHttpBinding(), "");
endpoint.Behaviors.Add(new NewtonsoftJsonBehavior());
serviceHost.Open();

方式B：配置文件注册行为

先注册行为扩展，再给端点绑定：

<system.serviceModel>
  <extensions>
    <behaviorExtensions>
      <!-- 替换成你的命名空间和程序集名称 -->
      <add name="newtonsoftJsonBehavior" type="YourNamespace.NewtonsoftJsonBehaviorElement, YourAssemblyName"/>
    </behaviorExtensions>
  </extensions>
  <behaviors>
    <endpointBehaviors>
      <behavior name="CamelCaseJsonBehavior">
        <newtonsoftJsonBehavior />
        <webHttp />
      </behavior>
    </endpointBehaviors>
  </behaviors>
  <services>
    <service name="YourNamespace.FormsConfigTool">
      <endpoint address="" behaviorConfiguration="CamelCaseJsonBehavior" 
                binding="webHttpBinding" contract="YourNamespace.IFormsConfigTool"/>
    </service>
  </services>
</system.serviceModel>

对应的行为元素类：

using System.ServiceModel.Configuration;

public class NewtonsoftJsonBehaviorElement : BehaviorExtensionElement
{
    public override Type BehaviorType => typeof(NewtonsoftJsonBehavior);

    protected override object CreateBehavior()
    {
        return new NewtonsoftJsonBehavior();
    }
}

总结 #

• 模型少、属性少：优先选方案一，简单快捷；
• 模型多、想自动转换：选方案二，一次配置全量生效，还能利用Json.NET的其他序列化特性。

内容的提问来源于stack exchange，提问作者Code-Strings