这是今天中午发生的事情,有人在群里求助,比如xml中如果标记是<xx:xxxx>content</xx:xxxx>这样的情况下,取不到 xx:xxxx 为下标的值。
看了这个问题,第一个反应就是namespace的关系,但我从来没有使用simplexml操作过namespace,于是就翻开手册查了一下资料,问题并没有解决,最终是通过google解决了该问题。
提问题的朋友贴出了数据源,来自于:http://code.google.com/intl/zh-CN/apis/contacts/docs/3.0/developers_guide_protocol.html#retrieving_without_query,数据结构大致如下:
- <feed xmlns='http://www.w3.org/2005/Atom' xmlns:openSearch='http://a9.com/-/spec/opensearch/1.1/' xmlns:gContact='http://schemas.google.com/contact/2008' xmlns:batch='http://schemas.google.com/gdata/batch' xmlns:gd='http://schemas.google.com/g/2005' gd:etag='W/"CUMBRHo_fip7ImA9WxRbGU0."'>
- <id>liz@gmail.com</id>
- <updated>2008-12-10T10:04:15.446Z</updated>
- <category scheme='http://schemas.google.com/g/2005#kind' term='http://schemas.google.com/contact/2008#contact' />
- <title>Elizabeth Bennet's Contacts</title>
- <link rel='http://schemas.google.com/g/2005#feed' type='application/atom+xml' href='https://www.google.com/m8/feeds/contacts/liz%40gmail.com/full' />
- <link rel='http://schemas.google.com/g/2005#post' type='application/atom+xml' href='https://www.google.com/m8/feeds/contacts/liz%40gmail.com/full' />
- <link rel='http://schemas.google.com/g/2005#batch' type='application/atom+xml' href='https://www.google.com/m8/feeds/contacts/liz%40gmail.com/full/batch' />
- <link rel='self' type='application/atom+xml' href='https://www.google.com/m8/feeds/contacts/liz%40gmail.com/full?max-results=25' />
- <author>
- <name>Elizabeth Bennet</name>
- <email>liz@gmail.com</email>
- </author>
- <generator version='1.0' uri='http://www.google.com/m8/feeds'> Contacts </generator>
- <openSearch:totalResults>1</openSearch:totalResults>
- <openSearch:startIndex>1</openSearch:startIndex>
- <openSearch:itemsPerPage>25</openSearch:itemsPerPage>
- <entry gd:etag='"Qn04eTVSLyp7ImA9WxRbGEUORAQ."'>
- <id> http://www.google.com/m8/feeds/contacts/liz%40gmail.com/base/c9012de </id>
- <updated>2008-12-10T04:45:03.331Z</updated>
- <app:edited xmlns:app='http://www.w3.org/2007/app'>2008-12-10T04:45:03.331Z</app:edited>
- <category scheme='http://schemas.google.com/g/2005#kind' term='http://schemas.google.com/contact/2008#contact' />
- <title>Fitzwilliam Darcy</title>
- <gd:name>
- <gd:fullName>Fitzwilliam Darcy</gd:fullName>
- </gd:name>
- <link rel='http://schemas.google.com/contacts/2008/rel#photo' type='image/*' href='https://www.google.com/m8/feeds/photos/media/liz%40gmail.com/c9012de' gd:etag='"KTlcZWs1bCp7ImBBPV43VUV4LXEZCXERZAc."' />
- <link rel='self' type='application/atom+xml' href='https://www.google.com/m8/feeds/contacts/liz%40gmail.com/full/c9012de' />
- <link rel='edit' type='application/atom+xml' href='https://www.google.com/m8/feeds/contacts/liz%40gmail.com/full/c9012de' />
- <gd:phoneNumber rel='http://schemas.google.com/g/2005#home' primary='true'> 456 </gd:phoneNumber>
- <gd:extendedProperty name='pet' value='hamster' />
- <gContact:groupMembershipInfo deleted='false' href='http://www.google.com/m8/feeds/groups/liz%40gmail.com/base/270f' />
- </entry>
- </feed>
这个结构在上面的地址里有,这个是我格式化过的XML数据,现在要取得类似于“<gd:phoneNumber rel='http://schemas.google.com/g/2005#home' primary='true'> 456 </gd:phoneNumber> ”中的值。
最终代码如下:
- $x = new SimpleXmlElement($str);
- foreach($x->entry as $t){
- echo $t->id . "<br >";
- echo $t->updated . "<br />";
- $namespaces = $t->getNameSpaces(true);
- $gd = $t->children($namespaces['gd']);
- echo $gd->phoneNumber;
- }
当然,如果不象上面这样写,也可以写成这样:
- $x = new SimpleXmlElement($str);
- foreach($x->entry as $t){
- echo $t->id . "<br >";
- echo $t->updated . "<br />";
- //$namespaces = $t->getNameSpaces(true);
- //注意这里与上面一段的区别
- $gd = $t->children('http://schemas.google.com/g/2005');
- echo $gd->phoneNumber;
- }
只是象第二种写法就属于硬编码了,这样不太好,万一哪天有变化,还得再更改N多代码。
问题接踵而来,比如象下面这段:
- <event:event>
- <event:sessionKey></event:sessionKey>
- <event:sessionName>Learn QB in Minutes</event:sessionName>
- <event:sessionType>9</event:sessionType>
- <event:hostWebExID></event:hostWebExID>
- <event:startDate>02/12/2009</event:startDate>
- <event:endDate>02/12/2009</event:endDate>
- <event:timeZoneID>11</event:timeZoneID>
- <event:duration>30</event:duration>
- <event:description></event:description>
- <event:status>NOT_INPROGRESS</event:status>
- <event:panelists></event:panelists>
- <event:listStatus>PUBLIC</event:listStatus>
- </event:event>
这种非标准的XML,没有定义命名空间,怎么办?在这种情况下,其实SimpleXmlElement就已经直接可以解决了,但是会报warnging,因为他认为event这个命名空间不存在。
解决方法是:
- $xml = @new SimpleXmlElement($str);//在前面加@抑止错误。
- echo "<pre>";
- print_r($xml);
目前看来,这种解决方法比较好。