php - How do I delete XML nodes in PHP based on the information inside of it?

Question

Preface: There are many questions similar to this that I've scoured through profusely. Nothing can quite answer what I need to do.

Here is my data structure. (obviously simplified)

<Upload>
    <tickets>
        <ticket>
            <ticket_number>123</ticket_number>
            <clerk>001</clerk>
            <property>
                <item>
                    <item_number>1</item>
                    <jewelry_metal>GOLD</jewelry_metal>
                </item>
                <item>
                    <item_number>2</item>
                    <jewelry_metal>SILVER</jewelry_metal>
                </item>
            </property>
        </ticket>
        <ticket>
            <ticket_number>456</ticket_number>
            <clerk>001</clerk>
            <property>
                <item>
                    <item_number>1</item>
                    <jewelry_metal></jewelry_metal>
                </item>
            </property>
        </ticket>
    <tickets>
<Upload>

I need to check the first item in each ticket, and if the <jewelry_metal> tag is empty, delete the entire <ticket>. I'm open to any suggestions at this point.

Answer 1

您最好的选择是使用 XPath 和 DomDocument。尝试这个：

<?php
$xmlstr = <<<XML
<?xml version='1.0'?>
<Upload>
    <tickets>
        <ticket>
            <ticket_number>123</ticket_number>
            <clerk>001</clerk>
            <property>
                <item>
                    <item_number>1</item_number>
                    <jewelry_metal>GOLD</jewelry_metal>
                </item>
                <item>
                    <item_number>2</item_number>
                    <jewelry_metal>SILVER</jewelry_metal>
                </item>
            </property>
        </ticket>
        <ticket>
            <ticket_number>456</ticket_number>
            <clerk>001</clerk>
            <property>
                <item>
                    <item_number>1</item_number>
                    <jewelry_metal></jewelry_metal>
                </item>
            </property>
        </ticket>
    </tickets>
</Upload>
XML;

$doc = new DOMDocument();
$doc->loadxml($xmlstr);

$xpath = new DOMXpath($doc);

foreach($xpath->query('//tickets/ticket/property/item[1]') as $key => $item) {
    if (empty($item->getElementsByTagName('jewelry_metal')->item(0)->nodeValue)) {
        $item->parentNode->removeChild($item);  
    }
}

echo $doc->saveXML();

输出将是：

<?xml version="1.0"?>
<Upload>
    <tickets>
        <ticket>
            <ticket_number>123</ticket_number>
            <clerk>001</clerk>
            <property>
                <item>
                    <item_number>1</item_number>
                    <jewelry_metal>GOLD</jewelry_metal>
                </item>
                <item>
                    <item_number>2</item_number>
                    <jewelry_metal>SILVER</jewelry_metal>
                </item>
            </property>
        </ticket>
        <ticket>
            <ticket_number>456</ticket_number>
            <clerk>001</clerk>
            <property>

            </property>
        </ticket>
    </tickets>
</Upload>

希望这可以帮助！

Answer 2

我建议您为此使用 Xpath 语言。让我们翻译：

我需要检查每张票中的第一项，如果<jewelry_metal>标签为空，则删除整个<ticket>

进入xpath：

//ticket[.//item[1]/jewelry_metal = ""]

这将查询所有要删除的元素。在这个问题中解释了要在 PHP 中使用 simplexml 运行这样的 xpath 查询，然后删除元素：

• PHP SimpleXML - 删除 xpath 节点

确保您已启用错误报告，因为您提供的有问题的 XML 已完全损坏。以防万一你没有注意到。