未定義の名前空間接頭辞

Question

私はヤフーの天気APIを使用しています

$result = file_get_contents('https://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20weather.forecast%20where%20woeid%20in%20(select%20woeid%20from%20geo.places(1)%20where%20text%3D%22Sarajevo%22)&format=xml&env=store%3A%2F%2Fdatatables.org%2Falltableswithkeys'); 
$xml = simplexml_load_string($result); 
//echo htmlspecialchars($result, ENT_QUOTES, 'UTF-8'); 
$xml->registerXPathNamespace('yweather', 'http://xml.weather.yahoo.com/ns/rss/1.0'); 
    $weather_location = $xml->channel->xpath('yweather:location'); 
    if(!empty($weather_location)){ 
     foreach($xml->channel->item as $item){ 

      $forecast = $item->xpath('yweather:forecast');  
      $time = time(); 
      $wdate = strtotime($forecast[$i]['day']); 

      echo "".(string)$wdate.""; // Wed  
      echo "<span><b>".(int)$forecast[$i]['high']."°</b>";// 8 
      echo "&nbsp;".(int)$forecast[$i]['low']."°</span>"; // 19  
     }    
} 

サンプルXML：

警告：にSimpleXMLElement :: XPathの（）[のSimpleXMLElementこれが結果です

<?xml version="1.0" encoding="UTF-8"?> 
<query xmlns:yahoo="http://www.yahooapis.com/v1/base.rng" 
    yahoo:count="1" yahoo:created="2016-03-31T10:56:53Z" yahoo:lang="en-US"> 
    <results> 
     <channel> 
      <yweather:units 
       xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" 
       distance="mi" pressure="in" speed="mph" temperature="F"/> 
      <title>Yahoo! Weather - Sarajevo, Federacija Bosne I Hercegovine, BA</title> 
      <link>http://us.rd.yahoo.com/dailynews/rss/weather/Country__Country/*https://weather.yahoo.com/country/state/city-943828/</link> 
      <description>Yahoo! Weather for Sarajevo, Federacija Bosne I Hercegovine, BA</description> 
      <language>en-us</language> 
      <lastBuildDate>Thu, 31 Mar 2016 12:56 PM CEST</lastBuildDate> 
      <ttl>60</ttl> 
      <yweather:location 
       xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" 
       city="Sarajevo" country="Bosnia and Herzegovina" region=" Federacija Bosne I Hercegovine"/> 
      <yweather:wind 
       xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" 
       chill="70" direction="270" speed="4"/> 
      <yweather:atmosphere 
       xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" 
       humidity="43" pressure="922.0" rising="0" visibility="16.1"/> 
      <yweather:astronomy 
       xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" 
       sunrise="6:27 am" sunset="7:14 pm"/> 
      <image> 
       <title>Yahoo! Weather</title> 
       <width>142</width> 
       <height>18</height> 
       <link>http://weather.yahoo.com</link> 
       <url>http://l.yimg.com/a/i/brand/purplelogo//uh/us/news-wea.gif</url> 
      </image> 
      <item> 
       <title>Conditions for Sarajevo, Federacija Bosne I Hercegovine, BA at 12:00 PM CEST</title> 
       <geo:lat xmlns:geo="http://www.w3.org/2003/01/geo/wgs84_pos#">43.853161</geo:lat> 
       <geo:long xmlns:geo="http://www.w3.org/2003/01/geo/wgs84_pos#">18.38493</geo:long> 
       <link>http://us.rd.yahoo.com/dailynews/rss/weather/Country__Country/*https://weather.yahoo.com/country/state/city-943828/</link> 
       <pubDate>Thu, 31 Mar 2016 12:00 PM CEST</pubDate> 
       <yweather:condition 
        xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" 
        code="32" date="Thu, 31 Mar 2016 12:00 PM CEST" 
        temp="69" text="Sunny"/> 
       <yweather:forecast 
        xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" 
        code="30" date="31 Mar 2016" day="Thu" high="70" 
        low="41" text="Partly Cloudy"/> 
       <yweather:forecast 
        xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" 
        code="28" date="01 Apr 2016" day="Fri" high="72" 
        low="50" text="Mostly Cloudy"/> 
       <yweather:forecast 
        xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" 
        code="30" date="02 Apr 2016" day="Sat" high="68" 
        low="44" text="Partly Cloudy"/> 
       <yweather:forecast 
        xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" 
        code="30" date="03 Apr 2016" day="Sun" high="69" 
        low="45" text="Partly Cloudy"/> 
       <yweather:forecast 
        xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" 
        code="30" date="04 Apr 2016" day="Mon" high="69" 
        low="47" text="Partly Cloudy"/> 
       <yweather:forecast 
        xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" 
        code="30" date="05 Apr 2016" day="Tue" high="69" 
        low="47" text="Partly Cloudy"/> 
       <yweather:forecast 
        xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" 
        code="30" date="06 Apr 2016" day="Wed" high="69" 
        low="47" text="Partly Cloudy"/> 
       <yweather:forecast 
        xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" 
        code="28" date="07 Apr 2016" day="Thu" high="66" 
        low="49" text="Mostly Cloudy"/> 
       <yweather:forecast 
        xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" 
        code="28" date="08 Apr 2016" day="Fri" high="58" 
        low="50" text="Mostly Cloudy"/> 
       <yweather:forecast 
        xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" 
        code="28" date="09 Apr 2016" day="Sat" high="58" 
        low="47" text="Mostly Cloudy"/> 
       <description>&lt;![CDATA[&lt;img src="http://l.yimg.com/a/i/us/we/52/32.gif"/&gt; 
&lt;BR /&gt; 
&lt;b&gt;Current Conditions:&lt;/b&gt; 
&lt;BR /&gt;Sunny 
&lt;BR /&gt; 
&lt;BR /&gt; 
&lt;b&gt;Forecast:&lt;/b&gt; 
&lt;BR /&gt; Thu - Partly Cloudy. High: 70Low: 41 
&lt;BR /&gt; Fri - Mostly Cloudy. High: 72Low: 50 
&lt;BR /&gt; Sat - Partly Cloudy. High: 68Low: 44 
&lt;BR /&gt; Sun - Partly Cloudy. High: 69Low: 45 
&lt;BR /&gt; Mon - Partly Cloudy. High: 69Low: 47 
&lt;BR /&gt; 
&lt;BR /&gt; 
&lt;a href="http://us.rd.yahoo.com/dailynews/rss/weather/Country__Country/*https://weather.yahoo.com/country/state/city-943828/"&gt;Full Forecast at Yahoo! Weather&lt;/a&gt; 
&lt;BR /&gt; 
&lt;BR /&gt; 
(provided by &lt;a href="http://www.weather.com" &gt;The Weather Channel&lt;/a&gt;) 
&lt;BR /&gt; 
]]&gt;</description> 
       <guid isPermaLink="false"/> 
      </item> 
     </channel> 
    </results> 
</query> 

.xpath]：/home/ugbosnia/public_html/blocks/weather/block.php 8行目の未定義の名前空間接頭辞

警告：にSimpleXMLElement :: XPathの（）[simplexmlelement.xpath]：xmlXPathEval：評価はライン8

に/home/ugbosnia/public_html/blocks/weather/block.phpで任意の提案を失敗しましたか？

Answer 1

channelは、ドキュメント要素の子ノードではありません。 XMLを読んだ場合、文書要素はqueryで、子はresultsです。

$channel = $xml->results->channel; 

あなたはそのxpath()メソッドを使用する前に、各SimpleXMLElementに名前空間を登録する必要があります：私は、独自の変数にchannelを格納示唆しています。あなたの場合は$xmlに登録しますが、$channelまたは$itemオブジェクトに登録しないでください。 $ xml = simplexml_load_string（$ result）;

$channel = $xml->results->channel; 
$channel->registerXPathNamespace('yweather', 'http://xml.weather.yahoo.com/ns/rss/1.0'); 

$weather_location = $channel->xpath('yweather:location'); 
if(!empty($weather_location)){ 
    foreach($channel->item as $item){ 
    $item->registerXPathNamespace('yweather', 'http://xml.weather.yahoo.com/ns/rss/1.0'); 

    $forecast = $item->xpath('yweather:forecast');  
    var_dump($forecast);  
    }  
} 

出力：あなたが唯一のこのオブジェクトの名前空間を登録する必要がありますので、

array(10) { 
    [0]=> 
    object(SimpleXMLElement)#8 (1) { 
    ["@attributes"]=> 
    array(6) { 
     ["code"]=> 
     string(2) "30" 
     ["date"]=> 
     string(11) "31 Mar 2016" 
     ["day"]=> 
     string(3) "Thu" 
     ["high"]=> 
     string(2) "70" 
     ["low"]=> 
     string(2) "41" 
     ["text"]=> 
     string(13) "Partly Cloudy" 
    } 
    } 
    [1]=> 
    object(SimpleXMLElement)#9 (1) { 
    ... 

DOMは、XPath式のために別のオブジェクトを使用しています。

$document = new DOMDocument(); 
$document->loadXml($result); 
$xpath = new DOMXpath($document); 
$xpath->registerNamespace('yweather', 'http://xml.weather.yahoo.com/ns/rss/1.0'); 

$weather_location = $xpath->evaluate('//yweather:location'); 
... 

Answer 2

がが原因である可能性がありMaking Yahoo Weather API request with OAuth 1