php解析cas返回的xml
    使用php进行cas验证时，对方返回这么一段xml

<cas:serviceResponse xmlns:cas='http://www.yale.edu/tp/cas'>

    <cas:authenticationSuccess>

        <cas:user>zhangjian</cas:user>

        <cas:language></cas:language>

    </cas:authenticationSuccess>

</cas:serviceResponse>

    于是使用php相关函数进行解析

$str = <<<EOT

<cas:serviceResponse xmlns:cas='http://www.yale.edu/tp/cas'>

    <cas:authenticationSuccess>

        <cas:user>zhangjian</cas:user>

        <cas:language></cas:language>

    </cas:authenticationSuccess>

</cas:serviceResponse>

EOT;





/*

$validateXML = simplexml_load_string($str);print_r($validateXML);

$successnode = $validateXML->authenticationSuccess[0];

var_dump($successnode);

*/



$xml = new DOMDocument();

$xml -> loadXML($str);

var_dump($xml);

    结果都解析不出来，哪位朋友遇到过请指点下，不甚感激！！！
------解决方案--------------------
SimpleXML也是PHP5后提供的一套简单易用的xml工具集，
不过它不适用于包含namespace（命名空间）的xml。
------解决方案--------------------
怎么会？

<xmp>

<?php

$str = <<<EOT

<cas:serviceResponse xmlns:cas='http://www.yale.edu/tp/cas'>

    <cas:authenticationSuccess>

        <cas:user>zhangjian</cas:user>

        <cas:language></cas:language>

    </cas:authenticationSuccess>

</cas:serviceResponse>

EOT;

 

 



$validateXML = simplexml_load_string($str, null, 0, 'cas', true);

print_r($validateXML);



$successnode = $validateXML->authenticationSuccess[0];

print_r($successnode);



 

$xml = new DOMDocument();

$xml -> loadXML($str);

print_r($xml);

SimpleXMLElement Object

(

    [authenticationSuccess] => SimpleXMLElement Object

        (

            [user] => zhangjian

            [language] => SimpleXMLElement Object

                (

                )



        )



)

SimpleXMLElement Object

(

    [user] => zhangjian

    [language] => SimpleXMLElement Object

        (

        )



)

DOMDocument Object

(

    [doctype] => 

    [implementation] => (object value omitted)

    [documentElement] =>&