If your application does not require that the external subset be read, set this feature to false to improve the performance. You should use this feature with caution if your application.
如果应用程序不需要读入那个外部子集，可以将该特性设为false以提高性能。
Browsers don't seem to currently support external or parameter entities in the internal subset, probably as a security measure.
浏览器目前似乎不支持内部子集中的外部实体或参数实体，这也许是一个安全措施。
It doesn't read DTDs in external files, but it also doesn't use any declarations within the document (called the internal subset) for validation.
它不读取外部文件中的DTD，也不使用文档中的任何声明(称为内部子集)来进行检验。
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