如何使用simplexml更改名称空间元素的值？

Question

我在尝试更改XML值，然后将其保存为XML。 当我更改没有命名空间的元素时工作正常。问题是，当我想要改变的值在一个名字空间中时，我可以找到并打印出来，但任何更改都会被忽略;像这样：

$ns = $xmlsingle->children('mynamespace'); 
foreach ($ns as $myelement) 
{ 
    echo "my element is: [$myelement]"; 
    //I can change it: 
    $myelement = "something else"; 
    echo "my element is now: [$myelement]"; //yay, value is changed! 
} 
//GREAT! 
//But when I save the XML back, the value is not changed... apparently the children method creates a new object; not a link to the existing object 
//So if I copy/paste the code above, I have the original value, not the changed value 
$ns2 = $xmlsingle->children('mynamespace'); 
foreach ($ns2 as $myelement) 
{ 
    echo "my element is UNCHANGED! [$myelement]"; 
} 
//So my change's not done when I save the XML. 
$xmlsingle->asXML(); //This XML is exacly the same as the original XML, without changes to the namespaced elements. 

**请忽略可能无法编译任何愚蠢的错误，我重新输入从我的原代码的文本，否则会过大;代码起作用，只要NAMESPACED元素的值在我将其放回到XML时保持不变。

我不是PHP专家，我不知道如何以任何其他方式访问命名空间元素......我如何更改这些值？我到处搜索，但只找到如何读取值的说明。

Answer 1

尝试这样：

$xml = ' 
<example xmlns:foo="bar"> 
    <foo:a>Apple</foo:a> 
    <foo:b>Banana</foo:b> 
    <c>Cherry</c> 
</example>'; 

$xmlsingle = new \SimpleXMLElement($xml); 
echo "<pre>\n\n"; 
echo $xmlsingle->asXML(); 
echo "\n\n"; 

$ns = $xmlsingle->children('bar'); 
foreach ($ns as $i => $myelement){ 
    echo "my element is: [$myelement] "; 

    //$myelement = "something else"; // <-- OLD 
    $ns->$i = 'something else'; // <-- NEW 

    echo "my element is now: [$myelement]"; //yay, value is changed! 
    echo "\n"; 
} 
echo "\n\n"; 
echo $xmlsingle->asXML(); 
echo "\n</pre>"; 

和结果应该是：

 

    
    
     Apple 
     Banana 
     Cherry 
    

    my element is: [Apple] my element is now: [something else] 
    my element is: [Banana] my element is now: [something else] 

    
    
     something else 
     something else 
     Cherry 
    

希望这有助于。