这是我的XML文件。
<body>
<div>
<p time="00:00:08"> </p>
<p time="00:00:10"> </p>
<p time="00:00:13"> </p>
</div>
</body>
现在，我想将time="00:00:12"添加到XML文件中，但要按递增顺序添加。因此，在添加此时间之前，我必须将该时间与其他时间进行比较，然后将其添加到适当的位置。
有人能建议我怎么做吗。一个示例代码将非常有用。
正如Gordon的回答中所建议的，我会将XML文件加载到SimpleXML中，附加节点，然后对其进行排序
我对下面的代码进行了注释，以便逐步进行解释。
<?php
// Open the XML file
$xml = file_get_contents("captions.xml");
// SimpleXml is an "easy" API to manipulate XML
// A SimpleXmlElement is any element, in this case it will be the <body>
// element as it is first in the file.
$timestamps = new SimpleXmlElement($xml);
// Add our new time entry to the <div> element inside <body>
$timestamps->div->addChild("p", null);
// Get the index of the last element (the one we just added)
$index = $timestamps->div->p->count()-1;
// Add a time attribute to the element we just added
$e = $timestamps->div->p[$index];
$e->addAttribute("time", "00:00:12");
// Replace it with the new one (with a time attribute)
$timestamps->div->p[$index] = $e;
// Sort the elements by time (I've used bubble sort here as it's in the top of my head)
// Make sure you're setting this here or in php.ini, otherwise we get lots of warnings :)
date_default_timezone_set("Europe/London");
/**
* The trick here is that SimpleXmlElement returns references for nearly
* everything. This means that if you say $c = $timestamps->div->p[0], changes
* you make to $c are made to $timestamps->div->p[0]. It's the same as calling
* $c =& $timestamps->div->p[0]. We use the keyword clone to avoid this.
*/
$dates = $timestamps->div->children();
$swapped = true;
while ($swapped) {
$swapped = false;
for ($i = 0; $i < $dates->count() - 1; $i++) {
$curTime = clone $dates[$i]->attributes()->time;
$nextTime = clone $dates[$i+1]->attributes()->time;
// Swap if current is later than next
if (strtotime($curTime) > strtotime($nextTime)) {
$dates[$i]->attributes()->time = $nextTime;
$dates[$i+1]->attributes()->time = $curTime;
$swapped = true;
break;
}
}
}
// Write back
echo $timestamps->asXml();
//$timestamps->asXml("captions.xml");