我有以下代码从 wolframalpha api 获取一些信息：
<?php
if(isset($_POST['q'])){
include 'WolframAlphaEngine.php';
$engine = new WolframAlphaEngine( '9QA6R9-VGL4AAURHU' );
$resp = $engine->getResults("$q");
$pod = $resp->getPods();
$pod1 = $pod[1];
foreach($pod1->getSubpods() as $subpod){
if($subpod->img){
$plaintext = $subpod->img;
break;
}
}
$pod2 = $pod[2];
foreach($pod2->getSubpods() as $subpod2){
if($subpod2->plaintext){
$plaintext2 = $subpod2->plaintext;
break;
}
}
$result = substr($plaintext, 0,strlen($plaintext)-3);
preg_match( '|img src="([^"]+)"|', $plaintext, $matches );
$img_src = $matches[1];
echo "$img_src<br><img src='$img_src'>";
echo "<br><br>";
echo $plaintext2;
}
?>
每个 subpod 中都有一个 img 标签。如何获取 img src 并显示图像？
我知道它在这里：
foreach($pod1->getSubpods() as $subpod){
if($subpod->img){
$plaintext = $subpod->img;
break;
}
}
这是上下文：
<queryresult success="true" error="false" numpods="10" datatypes="Species" timedout="" timedoutpods="" timing="2.944" parsetiming="0.076" parsetimedout="false" recalculate="" id="MSPa17911cd1c5fi21h72ac20000332e54b60gcg1bff" host="http://www4a.wolframalpha.com" server="44" related="http://www4a.wolframalpha.com/api/v2/relatedQueries.jsp?id=MSPa17921cd1c5fi21h72ac20000535d27652696856c&s=44" version="2.6">
<pod title="Input interpretation" scanner="Identity" id="Input" position="100" error="false" numsubpods="1">
<subpod title="">
<plaintext>dog (animal)</plaintext>
<img src="http://www4a.wolframalpha.com/Calculate/MSP/MSP17931cd1c5fi21h72ac2000021h88ec64ehf1h10?MSPStoreType=image/gif&s=44" alt="dog (animal)" title="dog (animal)" width="89" height="18"/>
</subpod>
</pod>
<pod title="Scientific name" scanner="Data" id="ScientificName:SpeciesData" position="200" error="false" numsubpods="1">
<subpod title="">
<plaintext>Canis lupus familiaris</plaintext>
<img src="http://www4a.wolframalpha.com/Calculate/MSP/MSP17941cd1c5fi21h72ac2000057i1ae7gc4986gdf?MSPStoreType=image/gif&s=44" alt="Canis lupus familiaris" title="Canis lupus familiaris" width="139" height="18"/>
</subpod>
</pod>
<pod title="Alternate scientific names" scanner="Data" id="AlternateScientificNames:SpeciesData" position="300" error="false" numsubpods="1">
<subpod title="">
<plaintext>Canis familiaris | Canis familiaris domesticus</plaintext>
<img src="http://www4a.wolframalpha.com/Calculate/MSP/MSP17951cd1c5fi21h72ac200004345f656d2010iea?MSPStoreType=image/gif&s=44" alt="Canis familiaris | Canis familiaris domesticus" title="Canis familiaris | Canis familiaris domesticus" width="301" height="18"/>
</subpod>
</pod>
<pod title="Taxonomy" scanner="Data" id="Taxonomy:SpeciesData" position="400" error="false" numsubpods="1">
<subpod title="">
<plaintext>
kingdom | Animalia (animals) phylum | Chordata (chordates) class | Mammalia (mammals) order | Carnivora (carnivores) family | Canidae (coyotes, dogs, foxes, jackals, wolves...) genus | Canis species | Canis lupus (gray wolf)
</plaintext>
<img src="http://www4a.wolframalpha.com/Calculate/MSP/MSP17961cd1c5fi21h72ac200003ec116f8g9gh4274?MSPStoreType=image/gif&s=44" alt="kingdom | Animalia (animals) phylum | Chordata (chordates) class | Mammalia (mammals) order | Carnivora (carnivores) family | Canidae (coyotes, dogs, foxes, jackals, wolves...) genus | Canis species | Canis lupus (gray wolf)" title="kingdom | Animalia (animals) phylum | Chordata (chordates) class | Mammalia (mammals) order | Carnivora (carnivores) family | Canidae (coyotes, dogs, foxes, jackals, wolves...) genus | Canis species | Canis lupus (gray wolf)" width="424" height="228"/>
</subpod>
<states count="1">
<state name="More" input="Taxonomy:SpeciesData__More"/>
</states>
</pod>
<pod title="Biological properties" scanner="Species" id="SpeciesDataPhysicalProperties" position="500" error="false" numsubpods="4">
<subpod title="Basic properties">
<plaintext>lifespan | (15 to 20) years</plaintext>
<img src="http://www4a.wolframalpha.com/Calculate/MSP/MSP17971cd1c5fi21h72ac2000067054fficad60e67?MSPStoreType=image/gif&s=44" alt="lifespan | (15 to 20) years" title="lifespan | (15 to 20) years" width="205" height="36"/>
</subpod>
<subpod title="Sensory organs">
<plaintext>
eyeball diameter | 0.83 inches (human: 0.94 in) eyeball volume | 0.31 in^3 (cubic inches) (human: 0.4 in^3) visual field | 250° (degrees) eardrum surface area | 46 mm^2 (square millimeters) (human: 55 mm^2) angle of auditory acuity | 2.5° (degrees) (human: 8.4°) upper limit of hearing ability | 140 kHz (kilohertz) (human: 21 kHz) olfactory epithelium receptor count | 2.3×10^8 (human: 3×10^7) olfactory epithelium surface area | 13 in^2 (square inches) (human: 0.39 to 0.78 in^2)
</plaintext>
<img src="http://www4a.wolframalpha.com/Calculate/MSP/MSP17981cd1c5fi21h72ac2000053f883b59b99g4c4?MSPStoreType=image/gif&s=44" alt="eyeball diameter | 0.83 inches (human: 0.94 in) eyeball volume | 0.31 in^3 (cubic inches) (human: 0.4 in^3) visual field | 250° (degrees) eardrum surface area | 46 mm^2 (square millimeters) (human: 55 mm^2) angle of auditory acuity | 2.5° (degrees) (human: 8.4°) upper limit of hearing ability | 140 kHz (kilohertz) (human: 21 kHz) olfactory epithelium receptor count | 2.3×10^8 (human: 3×10^7) olfactory epithelium surface area | 13 in^2 (square inches) (human: 0.39 to 0.78 in^2)" title="eyeball diameter | 0.83 inches (human: 0.94 in) eyeball volume | 0.31 in^3 (cubic inches) (human: 0.4 in^3) visual field | 250° (degrees) eardrum surface area | 46 mm^2 (square millimeters) (human: 55 mm^2) angle of auditory acuity | 2.5° (degrees) (human: 8.4°) upper limit of hearing ability | 140 kHz (kilohertz) (human: 21 kHz) olfactory epithelium receptor count | 2.3×10^8 (human: 3×10^7) olfactory epithelium surface area | 13 in^2 (square inches) (human: 0.39 to 0.78 in^2)" width="496" height="328"/>
</subpod>
<subpod title="Internal organs">
<plaintext>
brain weight | 4.8 oz (ounces) (human: 2.6 to 3.3 lb) heart weight | 4.8 oz (ounces) (human: 11 oz) cardiac output | (120 to 180) in^3/min (inches cubed per minute) (human: 340 to 370 in^3/min) interior lung surface area | 970 ft^2 (square feet) (human: 970 ft^2) stomach capacity | 1.1 gallons digestive tract capacity | 1.8 gallons length of whole intestine | 16 feet (human: 20 to 26 ft) small intestine capacity | 55 fl oz (fluid ounces) large intestine and rectum capacity | 31 fl oz (fluid ounces) appendix capacity | 3 fl oz (fluid ounces)
</plaintext>
<img src="http://www4a.wolframalpha.com/Calculate/MSP/MSP17991cd1c5fi21h72ac200005ec0d00i290h0gf3?MSPStoreType=image/gif&s=44" alt="brain weight | 4.8 oz (ounces) (human: 2.6 to 3.3 lb) heart weight | 4.8 oz (ounces) (human: 11 oz) cardiac output | (120 to 180) in^3/min (inches cubed per minute) (human: 340 to 370 in^3/min) interior lung surface area | 970 ft^2 (square feet) (human: 970 ft^2) stomach capacity | 1.1 gallons digestive tract capacity | 1.8 gallons length of whole intestine | 16 feet (human: 20 to 26 ft) small intestine capacity | 55 fl oz (fluid ounces) large intestine and rectum capacity | 31 fl oz (fluid ounces) appendix capacity | 3 fl oz (fluid ounces)" title="brain weight | 4.8 oz (ounces) (human: 2.6 to 3.3 lb) heart weight | 4.8 oz (ounces) (human: 11 oz) cardiac output | (120 to 180) in^3/min (inches cubed per minute) (human: 340 to 370 in^3/min) interior lung surface area | 970 ft^2 (square feet) (human: 970 ft^2) stomach capacity | 1.1 gallons digestive tract capacity | 1.8 gallons length of whole intestine | 16 feet (human: 20 to 26 ft) small intestine capacity | 55 fl oz (fluid ounces) large intestine and rectum capacity | 31 fl oz (fluid ounces) appendix capacity | 3 fl oz (fluid ounces)" width="496" height="409"/>
</subpod>
<subpod title="">
<plaintext>(typical values, except where otherwise noted)</plaintext>
<img src="http://www4a.wolframalpha.com/Calculate/MSP/MSP18001cd1c5fi21h72ac200005210724bc1978f7h?MSPStoreType=image/gif&s=44" alt="(typical values, except where otherwise noted)" title="(typical values, except where otherwise noted)" width="249" height="20"/>
</subpod>
<states count="2">
<state name="Show metric" input="SpeciesDataPhysicalProperties__Show metric"/>
<state name="More" input="SpeciesDataPhysicalProperties__More"/>
</states>
</pod>
<pod title="Genome information" scanner="Data" id="GenomeSummary:SpeciesData" position="600" error="false" numsubpods="1">
<subpod title="">
<plaintext>
total base pairs | 2445126910 total chromosomes | 39 known genes | 19528 known RNAs | 16953 known proteins | 33215
</plaintext>
<img src="http://www4a.wolframalpha.com/Calculate/MSP/MSP18011cd1c5fi21h72ac200006823c4b9b14245f8?MSPStoreType=image/gif&s=44" alt="total base pairs | 2445126910 total chromosomes | 39 known genes | 19528 known RNAs | 16953 known proteins | 33215" title="total base pairs | 2445126910 total chromosomes | 39 known genes | 19528 known RNAs | 16953 known proteins | 33215" width="260" height="164"/>
</subpod>
<states count="1">
<state name="Show details" input="GenomeSummary:SpeciesData__Show details"/>
</states>
</pod>
<pod title="Image" scanner="Data" id="Image:SpeciesData" position="700" error="false" numsubpods="1">
<subpod title="">
<plaintext/>
<img src="http://www4a.wolframalpha.com/Calculate/MSP/MSP18021cd1c5fi21h72ac200004030c96gcgd02f40?MSPStoreType=image/gif&s=44" alt="" title="" width="150" height="120"/>
</subpod>
</pod>
<pod title="Species authority" scanner="Data" id="SpeciesAuthorithy:SpeciesData" position="800" error="false" numsubpods="1">
<subpod title="">
<plaintext>Linnaeus</plaintext>
<img src="http://www4a.wolframalpha.com/Calculate/MSP/MSP18031cd1c5fi21h72ac200002c691ead7fc4927e?MSPStoreType=image/gif&s=44" alt="Linnaeus" title="Linnaeus" width="60" height="18"/>
</subpod>
</pod>
<pod title="Other members of species Canis lupus" scanner="Species" id="SpeciesScannerOtherMembersOfSpecies" position="900" error="false" numsubpods="1">
<subpod title="">
<plaintext>
Canis lupus subsp. lupus | Canis lupus subsp. lycaon
</plaintext>
<img src="http://www4a.wolframalpha.com/Calculate/MSP/MSP18041cd1c5fi21h72ac200000e76cgidc1b4a4fi?MSPStoreType=image/gif&s=44" alt="Canis lupus subsp. lupus | Canis lupus subsp. lycaon" title="Canis lupus subsp. lupus | Canis lupus subsp. lycaon" width="345" height="18"/>
</subpod>
</pod>
<pod title="Taxonomic network" scanner="Data" id="TaxonomyGraph:SpeciesData" position="1000" error="false" numsubpods="1">
<subpod title="">
<plaintext/>
<img src="http://www4a.wolframalpha.com/Calculate/MSP/MSP18051cd1c5fi21h72ac200002ff8ihic491e8e59?MSPStoreType=image/gif&s=44" alt="" title="" width="496" height="280"/>
</subpod>
<states count="1">
<state name="Show as network" input="TaxonomyGraph:SpeciesData__Show as network"/>
</states>
</pod>
<assumptions count="1">
<assumption type="Clash" word="dog" template="Assuming "${word}" is ${desc1}. Use as ${desc2} instead" count="3">
<value name="Species" desc="a species specification" input="*C.dog-_*Species-"/>
<value name="DogBreedClass" desc="a class of dog breeds" input="*C.dog-_*DogBreedClass-"/>
<value name="ExamplePage" desc="a general topic" input="*C.dog-_*ExamplePage-"/>
</assumption>
</assumptions>
<sources count="2">
<source url="http://www.wolframalpha.com/sources/GenomeSequenceDataSourceInformationNotes.html" text="Genome sequence data"/>
<source url="http://www.wolframalpha.com/sources/SpeciesDataSourceInformationNotes.html" text="Species data"/>
</sources>
</queryresult>
我想获取 img src 并显示该图像。