Question

在WCF REST服务中，我根据Accept HTTP标头中指定的值在JSON和XML之间切换响应序列化。我正在使用IDispatchMessageFormatter，如此处所述 - http://damianblog.com/2008/10/31/wcf-rest-dynamic-response/。

我正在使用Content-Type进行PUT和POST，但是在PUT和POST的情况下，它自己的IDispatchMessageFormatter.SerializeReply不会被执行。

唯一的问题是这只适用于GET请求，而不适用于PUT，POST，DELETE等。有人知道为什么吗？或者我遗漏了一些非常基本的东西：）

感谢。

Answer 1

Ok解决了问题.....当前代码只处理WebGetAttribute：

class WebHttpBehavior2Ex : WebHttpBehavior
{
    protected override IDispatchMessageFormatter GetReplyDispatchFormatter(OperationDescription operationDescription, 
                                                                           ServiceEndpoint endpoint)
    {
        WebGetAttribute webGetAttribute = operationDescription.Behaviors.Find<WebGetAttribute>();
        DynamicResponseTypeAttribute mapAcceptedContentTypeToResponseEncodingAttribute = 
            operationDescription.Behaviors.Find<DynamicResponseTypeAttribute>();

        if (webGetAttribute != null && mapAcceptedContentTypeToResponseEncodingAttribute != null) {
            // We need two formatters, since we don't know what type we will need until runtime
            webGetAttribute.ResponseFormat = WebMessageFormat.Json;
            IDispatchMessageFormatter jsonDispatchMessageFormatter = 
                base.GetReplyDispatchFormatter(operationDescription, endpoint);
            webGetAttribute.ResponseFormat = WebMessageFormat.Xml;
            IDispatchMessageFormatter xmlDispatchMessageFormatter = 
                base.GetReplyDispatchFormatter(operationDescription, endpoint);
            return new DynamicFormatter() { 
                jsonDispatchMessageFormatter = jsonDispatchMessageFormatter, 
                xmlDispatchMessageFormatter = xmlDispatchMessageFormatter };
        }
        return base.GetReplyDispatchFormatter(operationDescription, endpoint);
    }
}

相反，我们需要同时处理WebGet和WebInvoke属性，如下所示：

public class WebHttpBehaviorEx : WebHttpBehavior
{
    protected override IDispatchMessageFormatter GetReplyDispatchFormatter(OperationDescription operationDescription,
                                                                           ServiceEndpoint endpoint)
    {
        WebGetAttribute webGetAttribute = operationDescription.Behaviors.Find<WebGetAttribute>();
        WebInvokeAttribute webInvokeAttr = operationDescription.Behaviors.Find<WebInvokeAttribute>();
        DynamicResponseTypeAttribute mapAcceptedContentTypeToResponseEncodingAttribute =
            operationDescription.Behaviors.Find<DynamicResponseTypeAttribute>();

        if (webGetAttribute != null && mapAcceptedContentTypeToResponseEncodingAttribute != null)
        {
            // We need two formatters, since we don't know what type we will need until runtime
            webGetAttribute.ResponseFormat = WebMessageFormat.Json;
            IDispatchMessageFormatter jsonDispatchMessageFormatter =
                base.GetReplyDispatchFormatter(operationDescription, endpoint);
            webGetAttribute.ResponseFormat = WebMessageFormat.Xml;
            IDispatchMessageFormatter xmlDispatchMessageFormatter =
                base.GetReplyDispatchFormatter(operationDescription, endpoint);
            return new DynamicFormatter()
            {
                jsonDispatchMessageFormatter = jsonDispatchMessageFormatter,
                xmlDispatchMessageFormatter = xmlDispatchMessageFormatter
            };
        }
        else if (webInvokeAttr != null && mapAcceptedContentTypeToResponseEncodingAttribute != null)
        {
            // We need two formatters, since we don't know what type we will need until runtime
            webInvokeAttr.ResponseFormat = WebMessageFormat.Json;
            IDispatchMessageFormatter jsonDispatchMessageFormatter =
                base.GetReplyDispatchFormatter(operationDescription, endpoint);
            webInvokeAttr.ResponseFormat = WebMessageFormat.Xml;
            IDispatchMessageFormatter xmlDispatchMessageFormatter =
                base.GetReplyDispatchFormatter(operationDescription, endpoint);
            return new DynamicFormatter()
            {
                jsonDispatchMessageFormatter = jsonDispatchMessageFormatter,
                xmlDispatchMessageFormatter = xmlDispatchMessageFormatter
            };
        }
        return base.GetReplyDispatchFormatter(operationDescription, endpoint);
    }
}

Answer 2

对于过帐值，您应使用标题Content-Type。此标头通常用于此类操作。

作为参考，您可以查看http://en.wikipedia.org/wiki/List_of_HTTP_header_fields

在非“GET”方法的WCF响应中切换序列化b / w json和xml

2 个答案: