客户想在保存时校验 自定义的总金额字段 是否等于 数量*金额，可以使用python二开一个校验器，代码如下:
```python
import clr
clr.AddReference('System')
clr.AddReference('Kingdee.BOS')
clr.AddReference('Kingdee.BOS.Core')
from System import *
from Kingdee.BOS.Core import *
from Kingdee.BOS.Core.Validation import *
from Kingdee.BOS.Log import Logger
def OnAddValidators(e):
validator = OneValidator()
validator.EntityKey = "FBillHead"
validator.AlwaysValidate = True
e.Validators.Add(validator)
class OneValidator(AbstractValidator):
def Validate(self, dataEntities, validateContext,ctx):
for bill in dataEntities:
entrys = bill["POOrderEntry"]#采购订单明细实体
for entry in entrys:
seq = entry["Seq"]#序号
qty = entry["Qty"]#采购数量
