使用带有索引位置的addChild

我知道 Artefacto's answer 已被接受,但它似乎正在做更多的工作比需要的。一个更简单的选择,使用他的函数签名,可以像下面的函数。

function addchild_at(SimpleXMLElement $sxml, $tagname, $i)
{
    $parent = dom_import_simplexml($sxml);
    $child  = $parent->ownerDocument->createElement($tagname);
    $target = $parent->getElementsByTagname('*')->item($i);
    if ($target === NULL) {
        $parent->appendChild($child);
    } else {
        $parent->insertBefore($child, $target);
    }
}

dom_import_simplexml .

$_RenderedXML = new SimpleXMLElement($_XML);

//Add a new Link node
addchild_at($_RenderedXML->Menu, "Link", 2);
$_RenderedXML->Menu->Link[2]->addAttribute("href", "page3.htm");


function addchild_at(SimpleXMLElement $sxml, $tagname, $i) {
    $elem = dom_import_simplexml($sxml);
    $new = $elem->ownerDocument->createElement($tagname);
    $chnodes = array();
    foreach ($elem->childNodes as $cn) {
        $chnodes[] = $cn;
    }
    $chnodes = array_filter($chnodes,
        function (DOMNode $dn) { return $dn->nodeType == XML_ELEMENT_NODE; }
    );
    $chnodes = array_values($chnodes);

    if ($i < count($chnodes))
        $elem->insertBefore($new, $chnodes[$i]);
    else
        $elem->appendChild($new);
}