function.is-scalar.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>Finds whether a variable is a scalar</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-resource.html">is_resource</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.is-string.html">is_string</a></div> <div class="up"><a href="ref.var.html">Variable handling Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div><hr /><div id="function.is-scalar" class="refentry"> <div class="refnamediv"> <h1 class="refname">is_scalar</h1> <p class="verinfo">(PHP 4 >= 4.0.5, PHP 5)</p><p class="refpurpose"><span class="refname">is_scalar</span> — <span class="dc-title"> Finds whether a variable is a scalar </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_scalar</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">$var</tt></span> )</div> <p class="para rdfs-comment"> Finds whether the given variable is a scalar. </p> <p class="para"> Scalar variables are those containing an <a href="language.types.integer.html" class="type integer">integer</a>, <a href="language.types.float.html" class="type float">float</a>, <a href="language.types.string.html" class="type string">string</a> or <a href="language.types.boolean.html" class="type boolean">boolean</a>. Types <a href="language.types.array.html" class="type array">array</a>, <a href="language.types.object.html" class="type object">object</a> and <a href="language.types.resource.html" class="type resource">resource</a> are not scalar. </p> <blockquote><p><b class="note">Note</b>: <b>is_scalar()</b> does not consider <a href="language.types.resource.html" class="type resource">resource</a> type values to be scalar as resources are abstract datatypes which are currently based on integers. This implementation detail should not be relied upon, as it may change. <br /> </p></blockquote> </div> <div class="refsect1 parameters"> <h3 class="title">Parameters</h3> <p class="para"> <dl> <dt> <span class="term"><i><tt class="parameter">var</tt></i></span> <dd> <p class="para"> The variable being evaluated. </p> </dd> </dt> </dl> </p> </div> <div class="refsect1 returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> Returns <b><tt>TRUE</tt></b> if <i><tt class="parameter">var</tt></i> is a scalar <b><tt>FALSE</tt></b> otherwise. </p> </div> <div class="refsect1 examples"> <h3 class="title">Examples</h3> <p class="para"> <div class="example"> <p><b>Example #1 <b>is_scalar()</b> example</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br /></span><span style="color: #007700">function </span><span style="color: #0000BB">show_var</span><span style="color: #007700">(</span><span style="color: #0000BB">$var</span><span style="color: #007700">) <br />{<br /> if (</span><span style="color: #0000BB">is_scalar</span><span style="color: #007700">(</span><span style="color: #0000BB">$var</span><span style="color: #007700">)) {<br /> echo </span><span style="color: #0000BB">$var</span><span style="color: #007700">;<br /> } else {<br /> </span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$var</span><span style="color: #007700">);<br /> }<br />}<br /></span><span style="color: #0000BB">$pi </span><span style="color: #007700">= </span><span style="color: #0000BB">3.1416</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$proteins </span><span style="color: #007700">= array(</span><span style="color: #DD0000">"hemoglobin"</span><span style="color: #007700">, </span><span style="color: #DD0000">"cytochrome c oxidase"</span><span style="color: #007700">, </span><span style="color: #DD0000">"ferredoxin"</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">show_var</span><span style="color: #007700">(</span><span style="color: #0000BB">$pi</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">show_var</span><span style="color: #007700">(</span><span style="color: #0000BB">$proteins</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>3.1416array(3) { [0]=> string(10) "hemoglobin" [1]=> string(20) "cytochrome c oxidase" [2]=> string(10) "ferredoxin"}</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.is-float.html" class="function" rel="rdfs-seeAlso">is_float()</a></li> <li class="member"><a href="function.is-int.html" class="function" rel="rdfs-seeAlso">is_int()</a></li> <li class="member"><a href="function.is-numeric.html" class="function" rel="rdfs-seeAlso">is_numeric()</a></li> <li class="member"><a href="function.is-real.html" class="function" rel="rdfs-seeAlso">is_real()</a></li> <li class="member"><a href="function.is-string.html" class="function" rel="rdfs-seeAlso">is_string()</a></li> <li class="member"><a href="function.is-bool.html" class="function" rel="rdfs-seeAlso">is_bool()</a></li> <li class="member"><a href="function.is-object.html" class="function" rel="rdfs-seeAlso">is_object()</a></li> <li class="member"><a href="function.is-array.html" class="function" rel="rdfs-seeAlso">is_array()</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-resource.html">is_resource</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.is-string.html">is_string</a></div> <div class="up"><a href="ref.var.html">Variable handling 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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