新开发了一个单据，修改的时候提示如下错误Object reference ...

[{"operation":"872cffbc-df12-429d-adf7-8ca8c5e12cdf.LoadData"}]
发生时间：17:06:55
错误来源： mscorlib
错误信息：Object reference not set to an instance of an object.
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调用堆栈：

Server stack trace:
at Kingdee.BOS.App.Core.BusinessDataReader.GetItemClassFieldWhere(BusinessInfo businessInfo, DynamicObject obj)
at Kingdee.BOS.App.Core.BusinessDataReader.LoadSingle(Object pk, BusinessInfo businessInfo, OQLFilter oFilter, Boolean loadReferenceData)

Exception rethrown at [0]:
at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)
at Kingdee.BOS.Contracts.IViewService.LoadSingle(Context ctx, Object pk, BusinessInfo businessInfo, OQLFilter ofilter)
at Kingdee.BOS.ServiceHelper.BusinessDataServiceHelper.LoadSingle(Context ctx, Object pk, BusinessInfo businessInfo, OQLFilter ofilter)
at Ki