Question

创建一个xml文件：

<book id="1">
  <chapter id="1">
    ...
  </chapter>
  <chapter id="2">
    ...
  </chapter>
  <chapter id="3">
    ...
  </chapter>
</book>

我如何计算内部的节点......？在上面的例子中，函数应该转为3，因为存在三个节点。

注意： 我访问...所以：

$xpath = new DOMXPath($filename);
$book = $xpath->query("//book[@id='1']")->item(0);

Answer 1

你可以这样做：

参考：http://de2.php.net/manual/en/book.dom.php

<script>

  // set variables outside initMap() function to make them visible for other functions
  var waypts = [];
  var directionsService;
  var directionsDisplay;
  var map;

  // add waypoints 
  waypts.push({
        location: "winnipeg, mb",
        stopover: true
      });
  waypts.push({
        location: "spokane, wa",
        stopover: true
      });    

  function initMap() {
    // map setup
    directionsService = new google.maps.DirectionsService;
    directionsDisplay = new google.maps.DirectionsRenderer;
    map = new google.maps.Map(document.getElementById('map'), {
      zoom: 6,
      center: {lat: 41.85, lng: -87.65}
    });
    directionsDisplay.setMap(map);

    // calculate route
    calculateAndDisplayRoute(directionsService, directionsDisplay);
  }

  function calculateAndDisplayRoute(directionsService, directionsDisplay) {
    directionsService.route({
      origin:"Boston, MA",//document.getElementById('start').value,
      destination: "San Francisco, CA",//document.getElementById('end').value,
      waypoints: waypts,
      optimizeWaypoints: true,
      travelMode: 'DRIVING'
    }, function(response, status) {
      if (status === 'OK') {
        directionsDisplay.setDirections(response);
        var route = response.routes[0];
        var summaryPanel = document.getElementById('directions-panel');
        summaryPanel.innerHTML = '';
        // For each route, display summary information.
        for (var i = 0; i < route.legs.length; i++) {
          var routeSegment = i + 1;
          summaryPanel.innerHTML += '<b>Route Segment: ' + routeSegment +
              '</b><br>';
          summaryPanel.innerHTML += route.legs[i].start_address + ' to ';
          summaryPanel.innerHTML += route.legs[i].end_address + '<br>';
          summaryPanel.innerHTML += route.legs[i].distance.text + '<br><br>';
        }
      } else {
        window.alert('Directions request failed due to ' + status);
      }
    });
  }

 function removewaypoint(idx=0) {
  // this function takes index of location to remove
  // point A is start
  // point B has index 0
  // point C has index 1... 
  // removewaypoint(1) - will remove point C

  waypts.splice(idx, 1);

  // recalculate route with new waypoints
  calculateAndDisplayRoute(directionsService, directionsDisplay);
 }
</script>

除非您可以使用此：

$dom->getElementsByTagName('chapter')->length;

Answer 2

试试此代码

function xml2array($xmlObject, $out = array()) {
    foreach ((array) $xmlObject as $index => $node)
        $out[$index] = ( is_object($node) ) ? xml2array($node) : $node;

    return $out;
}

$a = '<book>
<chapter id = "1">
...
</chapter>
<chapter id = "2">
...
</chapter>
<chapter id = "3">
...
</chapter>
</book>';
$a = simplexml_load_string($a);
$array=xml2array($a);
echo count($array['chapter']);

修改

使用DOMXpath试试这个

echo $book = $xpath->query("//book[@id='1']/chapter")->length;

如何获取xml文件中的节点数？

2 个答案: