业务需求和C#的插件实现，参考文章：【二开实现单据录入携带序列号主档备注信息】，重写一个Python版本的实现，供参考。

clr.AddReference("System.Core")
clr.AddReference("Kingdee.BOS")
clr.AddReference("Kingdee.BOS.Core")
clr.AddReference("Kingdee.BOS.DataEntity")
clr.AddReference('Kingdee.BOS.ServiceHelper')
clr.AddReference('Kingdee.BOS.Contracts')
clr.AddReference("Kingdee.K3.SCM.Stock.Business.PlugIn")
clr.AddReference("Kingdee.K3.Core")
clr.AddReference("Kingdee.K3.BD.ServiceHelper")

from System import *
from Kingdee.BOS.Log import Logger
from Kingdee.BOS import *
from Kingdee.BOS.Core import *
from System import StringComparison
from System.Collections.Generic import List
from Kingdee.BOS.ServiceHelper import *
from Kingdee.BOS.Core.Metadata.EntityElement import *
from Kingdee.BOS.Core.DynamicForm.PlugIn.Args import *
from Kingdee.K3.SCM.Stock.Business.PlugIn import *
from Kingdee.BOS.Orm.DataEntity import *
from Kingdee.K3.Core.SCM.STK import *
from Kingdee.K3.BD.ServiceHelper import *
from Kingdee.BOS.Core.Metadata.FieldElement import *
from Kingdee.BOS.Core.Metadata import *

def DataChanged(e):
    if e.Field.Key.Equals("FSNQTY", StringComparison.OrdinalIgnoreCase):
         if Convert.ToInt64(e.NewValue) > Convert.ToInt64(e.OldValue):
             DoSerialNoDataChanged(e)
 
def DoSerialNoDataChanged(e):
    for entity in this.Model.BusinessInfo.Entrys:
        if type(entity) is SNSubEntryEntity:
            parRowIndex = this.View.Model.GetEntryCurrentRowIndex(entity.ParentEntity.Key)
            entityDataObject = this.View.Model.GetEntityDataObject(entity.ParentEntity, parRowIndex)
            if entityDataObject != None:
                dataEntrys = entity.DynamicProperty.GetValue(entityDataObject)
                field = this.View.BusinessInfo.GetField("FMaterialId")
                dyObj = field.DynamicProperty.GetValue[DynamicObject](entityDataObject)
                materialId = 0
                if dyObj != None:
                    materialId = Convert.ToInt64(dyObj["msterID"])
                    
                field = this.View.BusinessInfo.MainOrgField 
                dyObj = field.DynamicProperty.GetValue[DynamicObject](entityDataObject.Parent)
                orgId = 0
                if dyObj != None:
                    orgId = Convert.ToInt64(dyObj["Id"])
                if materialId <= 0 or orgId <= 0:
                    return
                    
                _baseDataOrgCtl = Common.GetInvBaseDataCtrolType(this.View.Context)
                if dataEntrys != None and dataEntrys.Count > 0:
                    for item in dataEntrys:
                        strSerialNO = Convert.ToString(item["SerialNo"])
                        if item["SerialNote"] != None and item["SerialNote"].ToString() != "":  
                            continue
                        rets = SerialServiceHelper.GetSerialByNumber(this.View.Context, _baseDataOrgCtl, strSerialNO, orgId, orgId, materialId, False, False)
                        if len(rets) > 0:
                            #SetBaseFieldValue(this.View.Context, this.View.BillBusinessInfo, "FSerialId", rets[0].Id, item)
                            SetBaseFieldValueByFilter(this.View.Context, rets[0].Id, item)
                            this.View.UpdateView(entity.Key, e.Row)
                            
# 直接查询序列号主档，比较通用，不用修改BOS添加字段引用，但是返回序列号数量多触发查询，对性能有影响                            
def SetBaseFieldValueByFilter(ctx, baseId, rowEntity):
    ofilter = OQLFilter()
    filteritem = OQLFilterHeadEntityItem()
    filteritem.FilterString = '''FSERIALID = {0} '''.format(str(baseId))
    ofilter.Add(filteritem);
    serialselector = List[SelectorItemInfo]();
    selectorItemInfo = SelectorItemInfo("FDescription")
    serialselector.Add(selectorItemInfo);
    serials = BusinessDataServiceHelper.Load(ctx, "BD_SerialMainFile", serialselector, ofilter)
    if len(serials) > 0:
        rowEntity["SerialNote"] = Convert.ToString(serials[0]["DESCRIPTION"]);
        this.View.UpdateView("FSerialNote")
        
# 加载基础资料的方式，需要序列号子单据体添加"备注"字段的引用        
def SetBaseFieldValue(ctx, businessinfo, baseKey, baseId, rowEntity):
    newValue = None
    field = businessinfo.GetField(baseKey)
    if baseId > 0:
        newValue = BusinessDataServiceHelper.LoadSingle(ctx, baseId, field.RefFormDynamicObjectType, None)
        
    field.RefIDDynamicProperty.SetValue(rowEntity, baseId)
    field.DynamicProperty.SetValue(rowEntity, newValue)
    if newValue != None:
        rowEntity["SerialNote"] = Convert.ToString(newValue["DESCRIPTION"])
        this.View.UpdateView("FSerialNote")

SerialBillEdit.rar

邱老师，这个注册python脚本之后不生效啊

老师有二开单据保存序列号主档的案例么?