错误信息:
A possible object cycle was detected which is not supported. This can either be due to a cycle or if the object depth is larger than the maximum allowed depth of 32.
造成此问题的原因是由于在生成Json对象的时候属性的循环引用导致的。
解决办法 :
services.AddControllersWithViews().AddNewtonsoftJson(options=>options.SerializerSettings.ReferenceLoopHandling=Newtonsoft.Json.ReferenceLoopHandling.Ignore);