Question

高手求教，PHP怎么向xml中插入新信息？

之前生成了一个XML文件

$doc = new DOMDocument('1.0', 'utf-8');
$doc -> formatOutput = true;
$folder = $doc -> createElement('folder');
$file = $doc -> createElement('file');

$pname = $doc -> createAttribute('pname');
$pclass = $doc -> createAttribute('class');
$pcar = $doc -> createAttribute('pcar');
$newspname = $doc -> createTextNode($name);
$newspclass = $doc -> createTextNode($_POST['Sclass']);
$newspcar = $doc -> createTextNode($_POST['Scar']);

$pname -> appendChild($newspname);
$pclass -> appendChild($newspclass);
$pcar -> appendChild($newspcar);

$file -> appendChild($pname);
$file -> appendChild($pclass);
$file -> appendChild($pcar);
$doc ->appendChild($folder);

$folder -> appendChild($file);
$doc -> save('ico/Thumb/'."pic.xml");
XML文件是这样的：

<?xml version="1.0" encoding="utf-8"?>
<folder>
<file pname="1336987243222652.jpg" class="1" pcar="测试"/>
</folder>
我想加一条<file pname="133698724000000.jpg" class="000" pcar="测试2"/>
我添加的语句是：

$doc = new DOMDocument();
$doc->load( 'ico/Thumb/'."pic.xml");

$folder = $doc->getElementsByTagName("folder");
$new_file=$doc->createElement("file");

$pname = $doc -> createAttribute('pname');
$pclass = $doc -> createAttribute('class');
$pcar = $doc -> createAttribute('pcar');

$newspname = $doc -> createTextNode($name);
$newspclass = $doc -> createTextNode($_POST['Sclass']);
$newspcar = $doc -> createTextNode($_POST['Scar']);

$pname -> appendChild($newspname);
$pclass -> appendChild($newspclass);
$pcar -> appendChild($newspcar);

$new_file -> appendChild($pname);
$new_file -> appendChild($pclass);
$new_file -> appendChild($pcar);

$folder -> appendChild($new_file);
$doc ->appendChild($folder);

$doc -> save('ico/Thumb/'."pic.xml");
然后就报错Call to undefined method DOMNodeList::appendChild() in C:\ProgramFiles\wamp\www\GraduateAlbumQ\user\up.php on line 73 求高手帮帮忙!

Answer 1

应该是这样：
$doc = new DOMDocument();
$doc->load( "pic.xml");
//这里你要获取他的第一个tag，因为getElementsByTagName获取的结果是个数组对象
$folder = $doc->getElementsByTagName("folder") -> item(0);

$new_file=$doc->createElement("file");

$pname = $doc -> createAttribute('pname');
$pclass = $doc -> createAttribute('class');
$pcar = $doc -> createAttribute('pcar');

$newspname = $doc -> createTextNode($name);
$newspclass = $doc -> createTextNode($_POST['Sclass']);
$newspcar = $doc -> createTextNode($_POST['Scar']);

$pname -> appendChild($newspname);
$pclass -> appendChild($newspclass);
$pcar -> appendChild($newspcar);

$new_file -> appendChild($pname);
$new_file -> appendChild($pclass);
$new_file -> appendChild($pcar);

$folder -> appendChild($new_file);
//$doc ->appendChild($folder);//前面已经append了，就不需要在append了

$doc -> save("pic.xml");