The __toString() method includes the XML header and namespace declarations required for correct use of the Activity Streams vocabulary. Listing 9 shows the addEntry() and __toString() methods

__toString() 方法包含了正确使用 Activity Streams 词汇表所需要的 XML 头和名称空间声明。

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IO namespace contains types that allow synchronous and asynchronous reading and writing on data streams and files.

IO命名空间包含允许对数据流和文件进行同步和异步读取及写入的类型。

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