Can multiple XML namespace declarations be in scope at the same time?

XML Interview Questions and Answers

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83. Can multiple XML namespace declarations be in scope at the same time?

Yes, as long as they don't use the same prefixes and at most one of them is the default XML namespace. For example, in the following, the http://www.google.org/ and http://www.bar.org/ namespaces are both in scope for all elements:
<A xmlns:google="http://www.google.org/"
xmlns:bar="http://www.bar.org/">
<google:B>abcd</google:B>
<bar:C>efgh</bar:C>
</A>
One consequence of this is that you can place all XML namespace declarations on the root element and they will be in scope for all elements. This is the simplest way to use XML namespaces.

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