Message in Chinese (Simplified) (中文(简体))
无法向该集合添加项目。当 DataServiceContext 跟踪 DataServiceCollection 中的项目时，在将新项目加载到该集合中之前，无法添加这些项目。
Unlocalized message
An item could not be added to the collection. When items in a DataServiceCollection are tracked by the DataServiceContext, new items cannot be added before items have been loaded into the collection.
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