Message in Chinese (Simplified) (中文(简体))
不能将属性“<var>Property Name</var>”的原始值设置为 null，因为实体类型“<var>Type Name</var>”上的“<var>X</var>”成员不可以为 null。
Unlocalized message
The original value for the property '<var>Property Name</var>' cannot be set to null because the '<var>X</var>' member on the entity type '<var>Type Name</var>' is not nullable.
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