AFNetwork 2.0在请求时报错 Error Domain=NSCocoaErrorDomain Code=3840

Domain=NSCocoaErrorDomain Code=3840 "The operation couldn’t be completed. (Cocoa error 3840.)" (JSON text did not start with array or object and option to allow fragments not set.) UserInfo=0x7a65fc20 {NSDebugDescription=JSON text did not start with array or object and option to allow fragments not set., NSUnderlyingError=0x78f174d0 "Request failed: not found (404)"}

这个问题是后台返回的数据问题，其实就是后台报错了，让后台自己查查什么错就行了，我这边就是后台写了一个bug，默默的改掉了。跟我们ios没关系的。