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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>Defines a set of constants for retrieval and mass-definition</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.apc-compile-file.html">apc_compile_file</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.apc-delete.html">apc_delete</a></div> <div class="up"><a href="ref.apc.html">APC Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div><hr /><div id="function.apc-define-constants" class="refentry"> <div class="refnamediv"> <h1 class="refname">apc_define_constants</h1> <p class="verinfo">(PECL apc:3.0.0-3.0.9)</p><p class="refpurpose"><span class="refname">apc_define_constants</span> — <span class="dc-title"> Defines a set of constants for retrieval and mass-definition </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>apc_define_constants</b></b></span> ( <span class="methodparam"><span class="type">string</span> <tt class="parameter">$key</tt></span> , <span class="methodparam"><span class="type">array</span> <tt class="parameter">$constants</tt></span> [, <span class="methodparam"><span class="type">bool</span> <tt class="parameter">$case_sensitive</tt></span> ] )</div> <p class="para rdfs-comment"> <a href="function.define.html" class="function">define()</a> is notoriously slow. Since the main benefit of APC is to increase the performance of scripts/applications, this mechanism is provided to streamline the process of mass constant definition. However, this function does not perform as well as anticipated. </p> <p class="para"> For a better-performing solution, try the <a href="http://pecl.php.net/package/hidef" class="link external">» hidef</a> extension from PECL. </p> <blockquote><p><b class="note">Note</b>: <span class="simpara"> To remove a set of stored constants (without clearing the entire cache), an empty array may be passed as the <i><tt class="parameter">constants</tt></i> parameter, effectively clearing the stored value(s). </span> </p></blockquote> </div> <div class="refsect1 parameters"> <h3 class="title">Parameters</h3> <p class="para"> <dl> <dt> <span class="term"><i><tt class="parameter">key</tt></i></span> <dd> <p class="para"> The <i><tt class="parameter">key</tt></i> serves as the name of the constant set being stored. This <i><tt class="parameter">key</tt></i> is used to retrieve the stored constants in <a href="function.apc-load-constants.html" class="function">apc_load_constants()</a>. </p> </dd> </dt> <dt> <span class="term"><i><tt class="parameter">constants</tt></i></span> <dd> <p class="para"> An associative array of <i>constant_name => value</i> pairs. The <i>constant_name</i> must follow the normal <a href="language.constants.html" class="link">constant</a> naming rules. <i>value</i> must evaluate to a scalar value. </p> </dd> </dt> <dt> <span class="term"><i><tt class="parameter">case_sensitive</tt></i></span> <dd> <p class="para"> The default behaviour for constants is to be declared case-sensitive; i.e. <i>CONSTANT</i> and <i>Constant</i> represent different values. If this parameter evaluates to <b><tt>FALSE</tt></b> the constants will be declared as case-insensitive symbols. </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> on success or <b><tt>FALSE</tt></b> on failure. </p> </div> <div class="refsect1 examples"> <h3 class="title">Examples</h3> <p class="para"> <div class="example"> <p><b>Example #1 <b>apc_define_constants()</b> example</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$constants </span><span style="color: #007700">= array(<br /> </span><span style="color: #DD0000">'ONE' </span><span style="color: #007700">=> </span><span style="color: #0000BB">1</span><span style="color: #007700">,<br /> </span><span style="color: #DD0000">'TWO' </span><span style="color: #007700">=> </span><span style="color: #0000BB">2</span><span style="color: #007700">,<br /> </span><span style="color: #DD0000">'THREE' </span><span style="color: #007700">=> </span><span style="color: #0000BB">3</span><span style="color: #007700">,<br />);<br /></span><span style="color: #0000BB">apc_define_constants</span><span style="color: #007700">(</span><span style="color: #DD0000">'numbers'</span><span style="color: #007700">, </span><span style="color: #0000BB">$constants</span><span style="color: #007700">);<br />echo </span><span style="color: #0000BB">ONE</span><span style="color: #007700">, </span><span style="color: #0000BB">TWO</span><span style="color: #007700">, </span><span style="color: #0000BB">THREE</span><span style="color: #007700">;<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>123</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.apc-load-constants.html" class="function" rel="rdfs-seeAlso">apc_load_constants()</a></li> <li class="member"><a href="function.define.html" class="function" rel="rdfs-seeAlso">define()</a></li> <li class="member"><a href="function.constant.html" class="function" rel="rdfs-seeAlso">constant()</a></li> <li class="member"> Or <a href="language.constants.html" class="link">the PHP constants reference</a> </li> </ul> </p> </div></div><hr /><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.apc-compile-file.html">apc_compile_file</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.apc-delete.html">apc_delete</a></div> <div class="up"><a href="ref.apc.html">APC 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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