C# Web API OPTION 跨域问题

C# Web API 由于默认对 OPTION 请求的不一样的处理，导致部分会通过 OPTION 请求来检测是否可跨域的浏览器，在跨域时总是还没开始就被拒绝。

处理办法

在 Web.config 中配置跨域，修改默认配置。

重点先行，注释掉以下这句

      <!--<remove name="OPTIONSVerbHandler" />-->

相关配置结果

  <system.webServer>
    <handlers>
      <remove name="ExtensionlessUrlHandler-Integrated-4.0" />
      <!--<remove name="OPTIONSVerbHandler" />-->
      <remove name="TRACEVerbHandler" />
      <add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="*" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0" />
    </handlers>
    <httpProtocol>
      <customHeaders>
        <add name="Access-Control-Allow-Origin" value="*" />
        <add name="Access-Control-Allow-Headers" value="Origin, X-Requested-With, Content-Type, Accept, WG-App-Version, WG-Device-Id, WG-Network-Type, WG-Vendor, WG-OS-Type, WG-OS-Version, WG-Device-Model, WG-CPU, WG-Sid, WG-App-Id, WG-Token, token" />
        <add name="Access-Control-Allow-Methods" value="POST, GET, OPTIONS, PUT, DELETE" />
        <add name="Access-Control-Allow-Credentials" value="false" />
      </customHeaders>
    </httpProtocol>
  </system.webServer>