Php 从xml url提取值

我需要从这个Url打印Identificator标记中的值，但是我没有得到任何输出

function get_xmlcontent(StdClass $data)
{
    $year       = $data->year;
    $course     = $data->clipid;
    $typeperiod = $data->typeperiod;    

    if ($typeperiod == 's'||$typeperiod == 'a') {
        $period = $data->period;
    } else if ($typeperiod == 't') {
        $period = $data->trimester;
    }

    //file from CLIP
    $xmlUrl = 'https://clip.unl.pt/sprs?lg=pt&year='.$year.'&uo=97747&srv=rsu&p='.$period.'&tp='.$typeperiod.'&md=3&rs='.$course.'&it=1030123459';

    $xmlStr = download_file_content($xmlUrl);
    $xmlObj = simplexml_load_string($xmlStr);
    foreach ($xmlObj->unidade_curricular->inscritos->aluno as $aluno) {
        echo $result = $aluno->identificador;
    }
}

---

如何解决此问题？

我使用file\u get\u contents（）并将xml字符串传递给SimpleXMLElement，而不是自定义的下载文件内容（）函数。希望这能为你指明正确的方向。 考虑在两种方法中拆分功能：a）BuffDILL（）b） 回答你的评论：这涉及到另一个问题！ 您的域是HTTPS域，因此您需要告诉cURL如何处理它。 我创建了一个示例，它解决了所有提到的问题并演示了 卷曲的用法

<?php

function buildURL($year, $period, $typeperiod, $course)
{
    return 'https://clip.unl.pt/sprs?lg=pt&year='.$year.'&uo=97747&srv=rsu&p='.$period.'&tp='.$typeperiod.'&md=3&rs='.$course.'&it=1030123459';
}

function doRequest_with_FileGetContents($url)
{
   return file_get_contents($url);
}

function doRequest_with_cURL($url) {
  $ch=curl_init();
  curl_setopt($ch,CURLOPT_URL, $url);
  curl_setopt($ch,CURLOPT_RETURNTRANSFER,1);

  // your domain is a HTTPS domain, so you need to tell curl how to deal with SSL verifications
  curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
  curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);

  $data=curl_exec($ch);
  curl_close($ch);

  return $data;
}

function processXML($xmlContent)
{
   $xmlObj = new SimpleXMLElement($xmlContent);

    foreach($xmlObj->unidade_curricular->inscritos->aluno as $aluno){
       $result= $aluno->identificador;
       echo $result;
    }
}

// Ok. Lets test..

// some testing values, i guess these will come from a formular
$year = '2013';
$period = '1';
$typeperiod = 's';
$course = '8145';

// a) build URL
$url = buildURL($year, $period, $typeperiod, $course);

// b) fetch content
$content_a = doRequest_with_cURL($url);

$content_b = doRequest_with_FileGetContents($url);

// c) process content (should be the same)
echo "\nRequest with cURL\n";
processXML($content_a);

echo "\nRequest with file_get_contents()\n";
processXML($content_b);

---

谢谢你的帮助。我试图构建一个curl函数来获取url信息，但是，我似乎无法将它与fetchxml函数联系起来。函数get_url（$year，$period，$typeperiod，$course）{$ch=curl_init（）；$timeout=5；curl_setopt（$ch，CURLOPT_url，'）；curl_setopt（$ch，CURLOPT_RETURNTRANSFER，1）；curl_setopt（$ch，CURLOPT_CONNECTTIMEOUT，$timeout）$data=curl_exec（$ch）；curl_close（$data；}我更新了最初的答案，并给出了一个curl用法的例子。如果你喜欢，就接受正确的答案。谢谢你。通过file\u get\u contents处理xml是可以的，但是通过curl会给我带来错误。致命错误：在C:\moodle25\server\moodle\local\ecoclipaluno\somefile.php:217堆栈跟踪：#0 C:\moodle25\server\moodle\local\ecoclipaluno\somefile.php（217）：SimpleXMLElement->\uu构造（“”）1 C:\moodle25\server\moodle\local\ecoclipaluno\somefile.php（235）：processXML（false）#2{main}在C:\moodle25\server\moodle\local\ecoclipaluno\somefile.php中抛出，位于第217行$xmlObj=new simplexmleElement（$xmlContent）；
<?php

function buildURL($year, $period, $typeperiod, $course)
{
    return 'https://clip.unl.pt/sprs?lg=pt&year='.$year.'&uo=97747&srv=rsu&p='.$period.'&tp='.$typeperiod.'&md=3&rs='.$course.'&it=1030123459';
}

function doRequest_with_FileGetContents($url)
{
   return file_get_contents($url);
}

function doRequest_with_cURL($url) {
  $ch=curl_init();
  curl_setopt($ch,CURLOPT_URL, $url);
  curl_setopt($ch,CURLOPT_RETURNTRANSFER,1);

  // your domain is a HTTPS domain, so you need to tell curl how to deal with SSL verifications
  curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
  curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);

  $data=curl_exec($ch);
  curl_close($ch);

  return $data;
}

function processXML($xmlContent)
{
   $xmlObj = new SimpleXMLElement($xmlContent);

    foreach($xmlObj->unidade_curricular->inscritos->aluno as $aluno){
       $result= $aluno->identificador;
       echo $result;
    }
}

// Ok. Lets test..

// some testing values, i guess these will come from a formular
$year = '2013';
$period = '1';
$typeperiod = 's';
$course = '8145';

// a) build URL
$url = buildURL($year, $period, $typeperiod, $course);

// b) fetch content
$content_a = doRequest_with_cURL($url);

$content_b = doRequest_with_FileGetContents($url);

// c) process content (should be the same)
echo "\nRequest with cURL\n";
processXML($content_a);

echo "\nRequest with file_get_contents()\n";
processXML($content_b);