php DOM XML在重新打开后使用换行符生成XML

Question

所以我有这个代码

$domDoc = new DOMDocument;
$rootElt = $domDoc->createElement('CONFIG');
$rootNode = $domDoc->appendChild($rootElt);

$subElt = $domDoc->createElement('APP-ID');
$subNode = $rootNode->appendChild($subElt);

$textNode = $domDoc->createTextNode('166533e56');
$subNode->appendChild($textNode);

$domDoc->save('config.xml');

生成

<CONFIG><APP-ID>166533e56</APP-ID></CONFIG>

这没有换行符。 当我添加

$domDoc->formatOutput = true;

就在代码的最后一行

之前

$domDoc->save('config.xml');

输出现在很好：

<CONFIG>
  <APP-ID>166533e56</APP-ID>
</CONFIG>

但是，当我在另一个php中尝试打开xml并在其中写入内容时，无论我尝试什么，它都会被无格式附加在那里。

在我做的另一个PHP代码中：

$domDoc = new DOMDocument;
$domDoc->load('config.xml');

$rootNode = $domDoc->documentElement;
$config_root = $rootNode->getElementsByTagName("CONFIG");

$rootElt = $domDoc->createElement('USER-ID');
$subNode = $rootNode->appendChild($rootElt);

$textNode = $domDoc->createTextNode('333265332f');
$subNode->appendChild($textNode);

$rootElt = $domDoc->createElement('USER-NAME');
$sub2Node = $rootNode->appendChild($rootElt);

$textNode = $domDoc->createTextNode('John');
$sub2Node->appendChild($textNode);

$domDoc->formatOutput = true;
$domDoc->save('config.xml');    

导致

<CONFIG>
  <APP-ID>166533e56</APP-ID>
<USER-ID>333265332f</USER-ID><USER-NAME>John</USER-NAME></CONFIG>

这是完全错误的。它应该是

<CONFIG>
  <APP-ID>166533e56</APP-ID>
  <USER-ID>333265332f</USER-ID>
  <USER-NAME>John</USER-NAME>
</CONFIG>

为什么没有添加换行符？我做错了什么？

Answer 1

在之前设置$domDoc->preserveWhiteSpace = false; ：您加载文件：

$domDoc = new DOMDocument;
$domDoc->preserveWhiteSpace = false;// <-- this line
$domDoc->loadXML(<<<XML
<?xml version="1.0"?>
<CONFIG>
  <APP-ID>166533e56</APP-ID>
</CONFIG>
XML
);

$rootNode = $domDoc->documentElement;
$config_root = $rootNode->getElementsByTagName("CONFIG");

$rootElt = $domDoc->createElement('USER-ID');
$subNode = $rootNode->appendChild($rootElt);

$textNode = $domDoc->createTextNode('333265332f');
$subNode->appendChild($textNode);

$rootElt = $domDoc->createElement('USER-NAME');
$sub2Node = $rootNode->appendChild($rootElt);

$textNode = $domDoc->createTextNode('John');
$sub2Node->appendChild($textNode);

$domDoc->formatOutput = true;
//$domDoc->save('config.xml');    
echo $domDoc->saveXML();

Live demo