PHP XML DOM 未捕获异常“DOMException”带有消息“错误文档错误”

Question

我正在尝试学习 XML，并且我知道这是由于未正确导入节点而导致的问题。但我不太明白。我环顾四周，大多数人没有像我对部门那样拥有多个子元素。

这是我的 XML 结构：

<SOT>  
    <DEPARTMENT name="Aviation Technology" id="AT">  
        <EMPLOYEE type="Faculty">  
            <LOGIN>jdoe1</LOGIN>  
            <NAME>John Doe</NAME>   
        </EMPLOYEE>

        <EMPLOYEE type="Faculty">  
            <LOGIN>jdoe2</LOGIN>  
            <NAME>Jane Doe</NAME>   
        </EMPLOYEE>

        <EMPLOYEE type="Faculty">  
            <LOGIN>jdoe3</LOGIN>  
            <NAME>Joe Doe</NAME>  
        </EMPLOYEE> 
    </DEPARTMENT>    

    <DEPARTMENT name="Building and Construction Management" id="BCM">  
    </DEPARTMENT>

    <DEPARTMENT name="Computer Graphics Technology" id="CGT">  
    </DEPARTMENT>  
</SOT>

我知道 SOT 是我的根元素，部门是 SOT 的“子元素”，每个部门都有多个员工“子元素”。我遇到的问题是当我尝试向某个部门添加新员工时。当我尝试 $departmentArray->item($i)->appendChild($employee); 时，出现错误文档错误。

我正在使用此 PHP 代码尝试将子级附加到部门节点。

<?php

    //grab form data
    $username = $_POST['username'];
    $employeeName = $_POST['employeeName'];
    $department = $_POST['department'];

    //create new DOMDocument to hold current XML data
    $doc = new DOMDocument();
    $doc->load("test.xml");
    $xpath = new DOMXpath($doc);

    //create our new DOMDocument for combining the XML data
    $newDoc = new DOMDocument();
    $newDoc->preserveWhiteSpace = false;

    //create School of Tech Node and append to new doc
    $sotElement = $newDoc->createElement("SOT");
    $newDoc->appendChild($sotElement);
    $root = $newDoc->documentElement;

    //grab the department Nodes
    $departmentArray = $doc->getElementsByTagName("DEPARTMENT");

    //create a new employee and set attribute to faculty
    $employee = $newDoc->createElement("EMPLOYEE");
    $employee->setAttribute("type", "Faculty");

    //counters (might use them later for ->item(counter) function
    $indexCounter = 0;
    $i = 0;

    foreach($departmentArray as $departmentNode){
        if(strcmp($departmentNode->getAttribute('name'),$department) == 0){//check if departments match
            //create login element
            $loginNode = $newDoc->createElement("LOGIN");
            $loginNode->appendChild($newDoc->createTextNode($username));
            $employee->appendChild($loginNode);

            //create name node
            $nameNode = $newDoc->createElement("NAME");
            $nameNode->appendChild($newDoc->createTextNode($employeeName));
            $employee->appendChild($nameNode);

            //append employee onto department node
            //$departmentArray->item($i) = $doc->importNode($departmentArray->item($i), true);
            $departmentArray->item($i)->appendChild($employee);

            //set index of department array (possibly used for appending later)
            $indexCounter = $i;
        }
        $i++;
    }

    #######################################
    /*Write out data to XML file         */
    #######################################
    //$departmentArray = $doc->getElementsByTagName("DEPARTMENT");
    foreach($departmentArray as $departmentNode){
        $tempNode = $newDoc->importNode($departmentNode, true);
        /*if(strcmp($departmentNode->getAttribute('name'),$department) == 0){
            $sotElement->appendChild($employee);

        }*/
        $sotElement->appendChild($tempNode);
    }

    $newDoc->formatOutput = true;
    $newDoc->save("test2.xml");


?>

如果有任何帮助解释如何正确导入所有部门节点以便能够附加到它们上，我们将不胜感激。我尝试过使用数组。

Answer 1

您需要导入任何节点才能将其附加到另一个文档：

$departmentArray->item($i)->appendChild( $doc->importNode( $employee, true ) );

Answer 2

我非常确定会发生这种情况，因为您正在尝试将不同文档中的元素附加到输出文档中。

我在 php 网站上 评论 中找到了这段代码 DOMNode::cloneNode 这可能就是你想要的。

<?php 
    $dom1->documentElement->appendChild( 
        $dom1->importNode( $dom2->documentElement, true )
    ); 
?>

或者，您可以考虑导出节点的 XML 并将其重新导入到 DOMDocumentFragment，但我必须尝试才能确定。