我在 SO 上看到了很多关于此的问题，但我找不到我的代码中缺少的内容。

我正在实现 CORS因为我不想使用 JSONP。

我知道这是一个preflighted request我想我正在添加正确的 headers。

错误是该网站似乎不喜欢我的 WCF 并且每次我发出请求时，都会调用一个 OPTION 方法，即使我有Access-Control-Allow-Methods header 。

我只想使用contentType: "application/json",

WCF 是自托管的，Web 应用程序在 IIS 7.5 上。

Chrome 显示的内容:

fiddler 显示了什么

契约(Contract)

<OperationContract()>
<WebInvoke(Method:="POST",
           RequestFormat:=WebMessageFormat.Json,
           ResponseFormat:=WebMessageFormat.Json,
           BodyStyle:=WebMessageBodyStyle.WrappedRequest)>
<FaultContract(GetType(ServiceFault))>
Function LookUpPerson(person As Person) _
                     As List(Of Person)

app.config

<serviceHostingEnvironment multipleSiteBindingsEnabled="true" aspNetCompatibilityEnabled="true" />
<bindings>
  <webHttpBinding>
    <binding name="webHttpBindingWithJsonP"
             crossDomainScriptAccessEnabled="true">
      <security mode="None" />
    </binding>
  </webHttpBinding>
</bindings>

<services>
  <service name="Project.Services.Person">  
    <endpoint address="ws"  binding="wsHttpBinding"     contract="Project.Services.Interfaces.IPublic" />   
    <endpoint address=""    binding="webHttpBinding"    contract="Project.Services.Interfaces.IPublic"
              behaviorConfiguration="jsonBehavior"/>
    <host>
      <baseAddresses>
        <add baseAddress="http://localhost:8732/" />
      </baseAddresses>
    </host>
  </service>
</services>

<extensions>
  <behaviorExtensions>
    <add name="customHeaders"
         type="Project.Services.Utilities.EnableCrossOriginResourceSharingBehavior, Project.Services, Version=1.0.0.0, Culture=neutral"/>
  </behaviorExtensions>
</extensions>

<endpointBehaviors>
  <behavior name="jsonBehavior">
    <webHttp/>
    <customHeaders />
  </behavior>
</endpointBehaviors>

javascript

$.ajax({
    url: "http://192.168.0.61:8282/Project.Services.Person/LookUpPerson",
    type: "POST",
    contentType: "application/json",
    crossDomain: true,
    dataType: "json",
    data: { person: JSON.stringify(person) },
    success: function (data) {
        // doing something
    },
    error: function (error) {
        // doing something
    }
});

根据 http://enable-cors.org/server_wcf.html，在 WCF 上我有以下处理程序

Public Class CustomHeaderMessageInspector
        Implements IDispatchMessageInspector

        Private requiredHeaders As Dictionary(Of String, String)
        Public Sub New(headers As Dictionary(Of String, String))
            requiredHeaders = If(headers, New Dictionary(Of String, String)())
        End Sub

        Public Function AfterReceiveRequest(ByRef request As System.ServiceModel.Channels.Message,
                                            channel As System.ServiceModel.IClientChannel,
                                            instanceContext As System.ServiceModel.InstanceContext) _
                                        As Object _
                                        Implements System.ServiceModel.Dispatcher.IDispatchMessageInspector.AfterReceiveRequest
            Return Nothing
        End Function

        Public Sub BeforeSendReply(ByRef reply As System.ServiceModel.Channels.Message,
                                   correlationState As Object) _
                               Implements System.ServiceModel.Dispatcher.IDispatchMessageInspector.BeforeSendReply
            Dim httpHeader = TryCast(reply.Properties("httpResponse"), HttpResponseMessageProperty)
            For Each item In requiredHeaders
                httpHeader.Headers.Add(item.Key, item.Value)
            Next
        End Sub

    End Class

和

Public Class EnableCrossOriginResourceSharingBehavior
        Inherits BehaviorExtensionElement
        Implements IEndpointBehavior

        Public Sub AddBindingParameters(endpoint As ServiceEndpoint, bindingParameters As System.ServiceModel.Channels.BindingParameterCollection) _
                                        Implements System.ServiceModel.Description.IEndpointBehavior.AddBindingParameters

        End Sub

        Public Sub ApplyClientBehavior(endpoint As ServiceEndpoint, clientRuntime As System.ServiceModel.Dispatcher.ClientRuntime) _
                                         Implements System.ServiceModel.Description.IEndpointBehavior.ApplyClientBehavior

        End Sub

        Public Sub ApplyDispatchBehavior(endpoint As ServiceEndpoint, endpointDispatcher As System.ServiceModel.Dispatcher.EndpointDispatcher) _
                                        Implements System.ServiceModel.Description.IEndpointBehavior.ApplyDispatchBehavior
            Dim requiredHeaders = New Dictionary(Of String, String)()

            requiredHeaders.Add("Access-Control-Allow-Origin", "*")
            requiredHeaders.Add("Access-Control-Allow-Methods", "POST, GET, OPTIONS")
            requiredHeaders.Add("Access-Control-Allow-Headers", "Origin, Content-Type, Accept")
            requiredHeaders.Add("Access-Control-Max-Age", "1728000")

            endpointDispatcher.DispatchRuntime.MessageInspectors.Add(New CustomHeaderMessageInspector(requiredHeaders))
        End Sub

        Public Sub Validate(endpoint As ServiceEndpoint) _
            Implements System.ServiceModel.Description.IEndpointBehavior.Validate

        End Sub

        Public Overrides ReadOnly Property BehaviorType() As Type
            Get
                Return GetType(EnableCrossOriginResourceSharingBehavior)
            End Get
        End Property

        Protected Overrides Function CreateBehavior() As Object
            Return New EnableCrossOriginResourceSharingBehavior()
        End Function

    End Class

抱歉发了这么长的帖子，我想具体一点。

提前致谢。

更新

如果我使用 contentType: "text/plain" 我在 chrome 控制台上收到错误:

POST http://192.168.0.61:8282/Project.Services.Person/LookUpPerson 400 (Bad Request)

最佳答案

我遇到了同样的问题，这为我解决了。

改变

[WebInvoke(Method = "Post")]

到

[WebInvoke(Method = "*")]

因为虽然您接受POST，但现代浏览器总是会发送OPTIONS。

关于javascript - jQuery .ajax() 405(方法不允许)/跨域，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/23480763/