📄 function.is-subclass-of.html
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html> <head> <title>Checks if the object has this class as one of its parents</title> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> </head> <body><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.is-a.html">is_a</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.method-exists.html">method_exists</a></div> <div class="up"><a href="ref.classobj.html">Classes/Object Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div><hr /><div id="function.is-subclass-of" class="refentry"> <div class="refnamediv"> <h1 class="refname">is_subclass_of</h1> <p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">is_subclass_of</span> — <span class="dc-title">Checks if the object has this class as one of its parents</span></p> </div> <div class="refsect1 description"> <h3 class="title">Description</h3> <div class="methodsynopsis dc-description"> <span class="type">bool</span> <span class="methodname"><b><b>is_subclass_of</b></b></span> ( <span class="methodparam"><span class="type"><a href="language.pseudo-types.html#language.types.mixed" class="type mixed">mixed</a></span> <tt class="parameter">$object</tt></span> , <span class="methodparam"><span class="type">string</span> <tt class="parameter">$class_name</tt></span> )</div> <p class="para rdfs-comment"> Checks if the given <i><tt class="parameter">object</tt></i> has the class <i><tt class="parameter">class_name</tt></i> as one of its parents. </p> </div> <div class="refsect1 parameters"> <h3 class="title">Parameters</h3> <p class="para"> <dl> <dt> <span class="term"><i><tt class="parameter">object</tt></i></span> <dd> <p class="para"> A class name or an object instance </p> </dd> </dt> <dt> <span class="term"><i><tt class="parameter">class_name</tt></i></span> <dd> <p class="para"> The class name </p> </dd> </dt> </dl> </p> </div> <div class="refsect1 returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> This function returns <b><tt>TRUE</tt></b> if the object <i><tt class="parameter">object</tt></i>, belongs to a class which is a subclass of <i><tt class="parameter">class_name</tt></i>, <b><tt>FALSE</tt></b> otherwise. </p> </div> <div class="refsect1 changelog"> <h3 class="title">ChangeLog</h3> <p class="para"> <table class="informaltable"> <colgroup> <thead valign="middle"> <tr valign="middle"> <th colspan="1">Version</th> <th colspan="1">Description</th> </tr> </thead> <tbody valign="middle" class="tbody"> <tr valign="middle"> <td colspan="1" rowspan="1" align="left">5.0.3</td> <td colspan="1" rowspan="1" align="left"> You may also specify the <i><tt class="parameter">object</tt></i> parameter as a string (the name of the class) </td> </tr> </tbody> </colgroup> </table> </p> </div> <div class="refsect1 examples"> <h3 class="title">Examples</h3> <p class="para"> <div class="example"> <p><b>Example #1 <b>is_subclass_of()</b> example</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">// define a class<br /></span><span style="color: #007700">class </span><span style="color: #0000BB">WidgetFactory<br /></span><span style="color: #007700">{<br /> var </span><span style="color: #0000BB">$oink </span><span style="color: #007700">= </span><span style="color: #DD0000">'moo'</span><span style="color: #007700">;<br />}<br /><br /></span><span style="color: #FF8000">// define a child class<br /></span><span style="color: #007700">class </span><span style="color: #0000BB">WidgetFactory_Child </span><span style="color: #007700">extends </span><span style="color: #0000BB">WidgetFactory<br /></span><span style="color: #007700">{<br /> var </span><span style="color: #0000BB">$oink </span><span style="color: #007700">= </span><span style="color: #DD0000">'oink'</span><span style="color: #007700">;<br />}<br /><br /></span><span style="color: #FF8000">// create a new object<br /></span><span style="color: #0000BB">$WF </span><span style="color: #007700">= new </span><span style="color: #0000BB">WidgetFactory</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">$WFC </span><span style="color: #007700">= new </span><span style="color: #0000BB">WidgetFactory_Child</span><span style="color: #007700">();<br /><br />if (</span><span style="color: #0000BB">is_subclass_of</span><span style="color: #007700">(</span><span style="color: #0000BB">$WFC</span><span style="color: #007700">, </span><span style="color: #DD0000">'WidgetFactory'</span><span style="color: #007700">)) {<br /> echo </span><span style="color: #DD0000">"yes, \$WFC is a subclass of WidgetFactory\n"</span><span style="color: #007700">;<br />} else {<br /> echo </span><span style="color: #DD0000">"no, \$WFC is not a subclass of WidgetFactory\n"</span><span style="color: #007700">;<br />}<br /><br /><br />if (</span><span style="color: #0000BB">is_subclass_of</span><span style="color: #007700">(</span><span style="color: #0000BB">$WF</span><span style="color: #007700">, </span><span style="color: #DD0000">'WidgetFactory'</span><span style="color: #007700">)) {<br /> echo </span><span style="color: #DD0000">"yes, \$WF is a subclass of WidgetFactory\n"</span><span style="color: #007700">;<br />} else {<br /> echo </span><span style="color: #DD0000">"no, \$WF is not a subclass of WidgetFactory\n"</span><span style="color: #007700">;<br />}<br /><br /><br /></span><span style="color: #FF8000">// usable only since PHP 5.0.3<br /></span><span style="color: #007700">if (</span><span style="color: #0000BB">is_subclass_of</span><span style="color: #007700">(</span><span style="color: #DD0000">'WidgetFactory_Child'</span><span style="color: #007700">, </span><span style="color: #DD0000">'WidgetFactory'</span><span style="color: #007700">)) {<br /> echo </span><span style="color: #DD0000">"yes, WidgetFactory_Child is a subclass of WidgetFactory\n"</span><span style="color: #007700">;<br />} else {<br /> echo </span><span style="color: #DD0000">"no, WidgetFactory_Child is not a subclass of WidgetFactory\n"</span><span style="color: #007700">;<br />}<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> <div class="example-contents"><p>The above example will output:</p></div> <div class="example-contents"><pre><div class="cdata"><pre>yes, $WFC is a subclass of WidgetFactoryno, $WF is not a subclass of WidgetFactoryyes, WidgetFactory_Child is a subclass of WidgetFactory</pre></div> </pre></div> </div> </p> </div> <div class="refsect1 seealso"> <h3 class="title">See Also</h3> <p class="para"> <ul class="simplelist"> <li class="member"><a href="function.get-class.html" class="function" rel="rdfs-seeAlso">get_class()</a></li> <li class="member"><a href="function.get-parent-class.html" class="function" rel="rdfs-seeAlso">get_parent_class()</a></li> <li class="member"><a href="function.is-a.html" class="function" rel="rdfs-seeAlso">is_a()</a></li> </ul> </p> </div></div><hr /><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.is-a.html">is_a</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.method-exists.html">method_exists</a></div> <div class="up"><a href="ref.classobj.html">Classes/Object Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div></body></html>⌨️ 快捷键说明
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