如何向WCF服务添加跨域支持

Question

我正在尝试允许来自我在localhost:80托管的javascript应用程序的POST请求到托管在不同端口的WCF REStful服务,但不知何故它不起作用.我已经尝试在标题中添加自定义属性,并在我的服务JSONData方法中以编程方式添加它,但我仍然在我的响应中得到'405 Method not allowed'.这里适当的方法是什么？

这是我的界面:

namespace RestService
{
    public class RestServiceImpl : IRestServiceImpl
    {
        #region IRestServiceImpl Members

        public string JSONData()
        {
            HttpContext.Current.Response.AddHeader("Access-Control-Allow-Origin", "*");
            return "Your POST request";
        }

        #endregion
    }
}

和服务代码:

using System.ServiceModel;
using System.ServiceModel.Web;
using System.Web.Script.Services;

namespace RestService
{

    [ServiceContract]
    public interface IRestServiceImpl
    {
        [OperationContract]
        [ScriptMethod]
        [WebInvoke(Method = "POST",
            ResponseFormat = WebMessageFormat.Json,
            BodyStyle = WebMessageBodyStyle.Bare,
            UriTemplate = "export")]
        string JSONData();
    }
}

最后配置:

<?xml version="1.0"?>
<configuration>

  <system.web>
    <compilation debug="true" targetFramework="4.0" />
  </system.web>
  <system.serviceModel>
    <services>
      <service name="RestService.RestServiceImpl" behaviorConfiguration="ServiceBehaviour">
        <endpoint address ="" binding="webHttpBinding" contract="RestService.IRestServiceImpl" behaviorConfiguration="web">
        </endpoint>
      </service>
    </services>

    <behaviors>
      <serviceBehaviors>
        <behavior name="ServiceBehaviour">
          <serviceMetadata httpGetEnabled="true"/>
          <serviceDebug includeExceptionDetailInFaults="false"/>
        </behavior>
      </serviceBehaviors>
      <endpointBehaviors>
        <behavior name="web">
          <webHttp/>
        </behavior>
      </endpointBehaviors>
    </behaviors>
    <serviceHostingEnvironment multipleSiteBindingsEnabled="true" />
  </system.serviceModel>
  <system.webServer>
    <modules runAllManagedModulesForAllRequests="true"/>
    <httpProtocol>
      <customHeaders>
         <add name="Access-Control-Allow-Origin" value="*" />
      </customHeaders>
</httpProtocol>  
  </system.webServer>

</configuration>

Answer 1

这比Web.config版本更适合我:

创建一个 Global.asax

将此方法添加到Global.asax.cs:

using System.Web;

namespace StackOverflow
{
    public class Global : System.Web.HttpApplication
    {
        protected void Application_BeginRequest(object sender, EventArgs e)
        {
            HttpContext.Current.Response.AddHeader("Access-Control-Allow-Origin", "*");
            if (HttpContext.Current.Request.HttpMethod == "OPTIONS")
            {
                HttpContext.Current.Response.AddHeader("Access-Control-Allow-Methods", "GET, POST");
                HttpContext.Current.Response.AddHeader("Access-Control-Allow-Headers", "Content-Type, Accept");
                HttpContext.Current.Response.AddHeader("Access-Control-Max-Age", "1728000");
                HttpContext.Current.Response.End();
            }
        }
    }
}

参考:http://www.dotnet-tricks.com/Tutorial/wcf/X8QN260412-Calling-Cross-Domain-WCF-Service-using-Jquery.html

Answer 2

将这些节点添加到Web.config:

<configuration>
  <system.webServer>
    <httpProtocol>
      <customHeaders>
        <add name="Access-Control-Allow-Origin" value="*"/>
        <add name="Access-Control-Allow-Headers" value="Content-Type, Accept" />
        <add name="Access-Control-Allow-Methods" value="POST,GET,OPTIONS" />
        <add name="Access-Control-Max-Age" value="1728000" />
      </customHeaders>
    </httpProtocol>
  </system.webServer>
</configuration>

参考:http://theagilecoder.wordpress.com/2014/07/07/wcf-and-cors-no-access-control-allow-origin-header-is-present-on-the-requested-resource/

Answer 3

为非GET请求启用CORS需要的不仅仅是设置Access-Control-Allow-Origin标头 - 它还需要处理预检请求,这些OPTIONS请求会询问服务器是否可以安全地执行可能会更改数据的操作(例如,POST,PUT,DELETE )在发送实际请求之前.

我写了一篇关于为WCF添加CORS支持的博客文章.这不是最简单的实现,但希望帖子中的代码可以简单地复制/粘贴到您的项目中.该帖子可以在http://blogs.msdn.com/b/carlosfigueira/archive/2012/05/15/implementing-cors-support-in-wcf.aspx找到.