{"error":"The parameters dictionary contains a null entry for parameter 'channelId' of non-nullable type 'System.Int32' for method 'System.String LoadChannelItem(Int32, Int32, Int32, System.Nullable`1[System.Int32])' in 'GzWechat.Web.Controllers.BookController'. An optional parameter must be a reference type, a nullable type, or be declared as an optional parameter.\r\nParameter name: parameters"}