This example shows how to create namespaced XML elements.
Example #1 Working with XML namespaces
<?php
$xw = xmlwriter_open_memory();
xmlwriter_set_indent($xw, 1);
$res = xmlwriter_set_indent_string($xw, ' ');
xmlwriter_start_document($xw, '1.0', 'UTF-8');
// A first element
xmlwriter_start_element_ns($xw,'prefix', 'books', 'uri');
xmlwriter_start_attribute($xw, 'isbn');
xmlwriter_start_attribute_ns($xw, 'prefix', 'isbn', 'uri');
xmlwriter_end_attribute($xw);
xmlwriter_end_attribute($xw);
xmlwriter_text($xw, 'book1');
xmlwriter_end_element($xw);
xmlwriter_end_document($xw);
echo xmlwriter_output_memory($xw);
以上例程会输出：
<?xml version="1.0" encoding="UTF-8"?> <prefix:books isbn="" prefix:isbn="" xmlns:prefix="uri">book1</prefix:books>