Question

我正在尝试使用2个xml文件将数据放在列表中。我无法编辑一个Xml文件，第二个是我创建的种类的参考数据库。这两个文件都具有<rvXMLfilename>的公共字符串，如果两个xml文件字符串都匹配，我想从XML文件2中回显一个字符串。我试图将其写入php脚本，但无法使其正常工作。

$railunit = simplexml_load_file('railUnitList.xml');
$orders = simplexml_load_file('train.xml');

    foreach ($orders->xpath("//RailVehicleStateClass") as $traininfo):
    $rvXMLfilename=$traininfo->rvXMLfilename;
    $unitType=$traininfo->unitType;
    $unitNumber=$traininfo->unitNumber;
    $destinationTag=$traininfo->destinationTag;
    $loadWeightUSTons=$traininfo->loadWeightUSTons;

    echo "<tr>";
    echo "<td>";
    if($railunit->rvXMLfilename == $orders->rvXMLfilename){
        echo $railunit->unitType;
    }else{
        echo "error!";
    }

XML文件1

<?xml version="1.0"?>
<ScnLoader xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <trainList>
    <TrainLoader>
      <unitLoaderList>
        <RailVehicleStateClass>
          <rvXMLfilename>R8_SD40T-2_UP03.xml</rvXMLfilename>
          <unitType>US_DieselEngine</unitType>
          <loadWeightUSTons>14.2985783</loadWeightUSTons>
          <destinationTag>MDTLA</destinationTag>
          <unitNumber>8626</unitNumber>
        </RailVehicleStateClass>
        <RailVehicleStateClass>
          <rvXMLfilename>R8_SD40T-2_UP01.xml</rvXMLfilename>
          <unitType>US_DieselEngine</unitType>
          <loadWeightUSTons>14.2985792</loadWeightUSTons>
          <destinationTag>None</destinationTag>
          <unitNumber>4401</unitNumber>
        </RailVehicleStateClass>
        <RailVehicleStateClass>
          <rvXMLfilename>R8_SD40T-2_UP01.xml</rvXMLfilename>
          <unitType>US_DieselEngine</unitType>
          <loadWeightUSTons>14.2985783</loadWeightUSTons>
          <destinationTag>None</destinationTag>
          <unitNumber>4454</unitNumber>
        </RailVehicleStateClass>
      </unitLoaderList>
    </TrainLoader>
  </trainList>
</ScnLoader>

XML文件2

<railUnitList>
  <railUnit>
    <rvXMLfilename>R8_SD40T-2_UP01.xml</rvXMLfilename>
    <unitType>SD40-2T Locomotive</unitType>
    <reportingMark>UP</reportingMark>
    <axelCount>6</axelCount>
    <unitWeight></unitWeight>
    <unitLength>71</unitLength>
  </railUnit>
  <railUnit>
    <rvXMLfilename>R8_CoveredHopper_ACF2970_BN01.xml</rvXMLfilename>
    <unitType>Covered Hopper</unitType>
    <reportingMark>BN</reportingMark>
    <axelCount>4</axelCount>
    <unitWeight></unitWeight>
    <unitLength>60</unitLength>
  </railUnit>
  <railUnit>
    <rvXMLfilename>R8_C14Hopper_POTASH01.xml</rvXMLfilename>
    <unitType>Covered Hopper</unitType>
    <reportingMark>POTX</reportingMark>
    <axelCount>4</axelCount>
    <unitWeight></unitWeight>
    <unitLength>60</unitLength>
  </railUnit>
  <railUnit>
    <rvXMLfilename>Run8_Tank107BN01.xml</rvXMLfilename>
    <unitType>Tank</unitType>
    <reportingMark>BN</reportingMark>
    <axelCount>4</axelCount>
    <unitWeight></unitWeight>
    <unitLength>59</unitLength>
  </railUnit>
</railUnitList>

Answer 1

再次使用XPath查询获取您要查找的值。将所有文件名粘贴到数组中，以便以后进行比较。

<?php
$railunit = simplexml_load_file('railUnitList.xml');
$orders = simplexml_load_file('train.xml');

foreach ($railunit->railUnit as $railunit) {
    $key = (string)$railunit->unitType;
    $value = (string)$railunit->rvXMLfilename;
    $filenames[$key] = $value;
}

foreach ($orders->xpath("//RailVehicleStateClass") as $traininfo) {
    $rvXMLfilename=$traininfo->rvXMLfilename;
    $unitType=$traininfo->unitType;
    $unitNumber=$traininfo->unitNumber;
    $destinationTag=$traininfo->destinationTag;
    $loadWeightUSTons=$traininfo->loadWeightUSTons;

    echo "<tr>";
    echo "<td>";
    if(in_array($traininfo->rvXMLfilename, $filenames)){
        echo array_search($traininfo->rvXMLfilename, $filenames);
    } else {
        echo "error!";
    }
}

还要注意您在原始代码中使用$orders->rvXMLfilename。 PHP结构与XML结构相同，除非它是根元素的直接子元素，否则不能以这种方式引用该元素。

Answer 2

您的代码有几个问题。首先，您不能直接将SimpleXMLElement的值引用为例如$rvXMLfilename=$traininfo->rvXMLfilename;您需要将其转换为适当的类型。其次，rvXMLfilename不是$railunit的子级。我认为您可能想遍历$railunit中的值，并将每个值与从$orders XML中提取的值进行比较。此代码应实现您想要的：

foreach ($orders->xpath("//RailVehicleStateClass") as $traininfo) {
    $rvXMLfilename=(string)$traininfo->rvXMLfilename;
    $unitType=(string)$traininfo->unitType;
    $unitNumber=(int)$traininfo->unitNumber;
    $destinationTag=(string)$traininfo->destinationTag;
    $loadWeightUSTons=(float)$traininfo->loadWeightUSTons;
    echo "<tr>";
    echo "<td>";
    $message = "error!";
    foreach ($railunit->railUnit as $ru) {
        if((string)$ru->rvXMLfilename == $rvXMLfilename){
            $message = (string)$ru->unitType;
        }
    }
    echo $message;
}

输出（用于示例数据）

<tr><td>error!<tr><td>SD40-2T Locomotive<tr><td>SD40-2T Locomotive

比较2个xml文件的值并回显匹配

2 个答案: