A namespace can be declared on any element, allowing it to be recognized within the sub-tree defined by that element and all its children.

可以对任何元素声明名称空间，从而允许在由该元素及其所有子元素定义的子树内识别它。

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Normal canonicalization: When a sub-part of the XML is serialized, the ancestor element's context and all namespace declarations and attributes in the xmlns namespace are included.

常规规范化：当序列化XML的一部分时，祖先元素的上下文和所有的名称空间声明以及xmlns 名称空间中的属性都被包括进来。

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Normal canonicalization: When a sub-part of the XML is serialized, the ancestor element's context and all namespace declarations and attributes in the xmlns namespace are included.

常规规范化：当序列化XML的一部分时，祖先元素的上下文和所有的名称空间声明以及xmlns 名称空间中的属性都被包括进来。

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