function.unserialize.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>Creates a PHP value from a stored representation</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.strval.html">strval</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.unset.html">unset</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.unserialize" class="refentry"> <div class="refnamediv"> <h1 class="refname">unserialize</h1> <p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">unserialize</span> — <span class="dc-title"> Creates a PHP value from a stored representation </span></p> </div> <div class="refsect1 description"> <h3 class="title">Description</h3> <div class="methodsynopsis dc-description"> <span class="type"><a href="language.pseudo-types.html#language.types.mixed" class="type mixed">mixed</a></span> <span class="methodname"><b><b>unserialize</b></b></span> ( <span class="methodparam"><span class="type">string</span> <tt class="parameter">$str</tt></span> )</div> <p class="simpara"> <b>unserialize()</b> takes a single serialized variable and converts it back into a PHP value. </p> </div> <div class="refsect1 parameters"> <h3 class="title">Parameters</h3> <p class="para"> <dl> <dt> <span class="term"><i><tt class="parameter">str</tt></i></span> <dd> <p class="para"> The serialized string. </p> <p class="para"> If the variable being unserialized is an object, after successfully reconstructing the object PHP will automatically attempt to call the <b>__wakeup()</b> member function (if it exists). </p> <p class="para"> <blockquote><p><b class="note">Note</b>: <b>unserialize_callback_func directive</b><br /> It's possible to set a callback-function which will be called, if an undefined class should be instantiated during unserializing. (to prevent getting an incomplete <a href="language.types.object.html" class="type object">object</a> "__PHP_Incomplete_Class".) Use your <var class="filename">php.ini</var>, <a href="function.ini-set.html" class="function">ini_set()</a> or <var class="filename">.htaccess</var> to define 'unserialize_callback_func'. Everytime an undefined class should be instantiated, it'll be called. To disable this feature just empty this setting. <br /> </p></blockquote> </p> </dd> </dt> </dl> </p> </div> <div class="refsect1 returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> The converted value is returned, and can be a <a href="language.types.boolean.html" class="type boolean">boolean</a>, <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>, <a href="language.types.array.html" class="type array">array</a> or <a href="language.types.object.html" class="type object">object</a>. </p> <p class="para"> In case the passed string is not unserializeable, <b><tt>FALSE</tt></b> is returned and <i>E_NOTICE</i> is issued. </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">4.2.0</td> <td colspan="1" rowspan="1" align="left"> The directive unserialize_callback_func became available. </td> </tr> <tr valign="middle"> <td colspan="1" rowspan="1" align="left">4.0.0</td> <td colspan="1" rowspan="1" align="left"> When serializing an object, methods are not lost anymore. Please see the <a href="language.oop.serialization.html" class="link">Serializing Objects</a> for more information. </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>unserialize()</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">// Here, we use unserialize() to load session data to the<br />// $session_data array from the string selected from a database.<br />// This example complements the one described with serialize().<br /><br /></span><span style="color: #0000BB">$conn </span><span style="color: #007700">= </span><span style="color: #0000BB">odbc_connect</span><span style="color: #007700">(</span><span style="color: #DD0000">"webdb"</span><span style="color: #007700">, </span><span style="color: #DD0000">"php"</span><span style="color: #007700">, </span><span style="color: #DD0000">"chicken"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$stmt </span><span style="color: #007700">= </span><span style="color: #0000BB">odbc_prepare</span><span style="color: #007700">(</span><span style="color: #0000BB">$conn</span><span style="color: #007700">, </span><span style="color: #DD0000">"SELECT data FROM sessions WHERE id = ?"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$sqldata </span><span style="color: #007700">= array(</span><span style="color: #0000BB">$_SERVER</span><span style="color: #007700">[</span><span style="color: #DD0000">'PHP_AUTH_USER'</span><span style="color: #007700">]);<br />if (!</span><span style="color: #0000BB">odbc_execute</span><span style="color: #007700">(</span><span style="color: #0000BB">$stmt</span><span style="color: #007700">, &</span><span style="color: #0000BB">$sqldata</span><span style="color: #007700">) || !</span><span style="color: #0000BB">odbc_fetch_into</span><span style="color: #007700">(</span><span style="color: #0000BB">$stmt</span><span style="color: #007700">, &</span><span style="color: #0000BB">$tmp</span><span style="color: #007700">)) {<br /> </span><span style="color: #FF8000">// if the execute or fetch fails, initialize to empty array<br /> </span><span style="color: #0000BB">$session_data </span><span style="color: #007700">= array();<br />} else {<br /> </span><span style="color: #FF8000">// we should now have the serialized data in $tmp[0].<br /> </span><span style="color: #0000BB">$session_data </span><span style="color: #007700">= </span><span style="color: #0000BB">unserialize</span><span style="color: #007700">(</span><span style="color: #0000BB">$tmp</span><span style="color: #007700">[</span><span style="color: #0000BB">0</span><span style="color: #007700">]);<br /> if (!</span><span style="color: #0000BB">is_array</span><span style="color: #007700">(</span><span style="color: #0000BB">$session_data</span><span style="color: #007700">)) {<br /> </span><span style="color: #FF8000">// something went wrong, initialize to empty array<br /> </span><span style="color: #0000BB">$session_data </span><span style="color: #007700">= array();<br /> }<br />}<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> </div> </p> <p class="para"> <div class="example"> <p><b>Example #2 unserialize_callback_func example</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$serialized_object</span><span style="color: #007700">=</span><span style="color: #DD0000">'O:1:"a":1:{s:5:"value";s:3:"100";}'</span><span style="color: #007700">;<br /><br /></span><span style="color: #FF8000">// unserialize_callback_func directive available as of PHP 4.2.0<br /></span><span style="color: #0000BB">ini_set</span><span style="color: #007700">(</span><span style="color: #DD0000">'unserialize_callback_func'</span><span style="color: #007700">, </span><span style="color: #DD0000">'mycallback'</span><span style="color: #007700">); </span><span style="color: #FF8000">// set your callback_function<br /><br /></span><span style="color: #007700">function </span><span style="color: #0000BB">mycallback</span><span style="color: #007700">(</span><span style="color: #0000BB">$classname</span><span style="color: #007700">) <br />{<br /> </span><span style="color: #FF8000">// just include a file containing your classdefinition<br /> // you get $classname to figure out which classdefinition is required<br /></span><span style="color: #007700">}<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> </div> </p> </div> <div class="refsect1 notes"> <h3 class="title">Notes</h3> <div class="warning"><b class="warning">Warning</b> <p class="para"> <b><tt>FALSE</tt></b> is returned both in the case of an error and if unserializing the serialized <b><tt>FALSE</tt></b> value. It is possible to catch this special case by comparing <i><tt class="parameter">str</tt></i> with <i>serialize(false)</i> or by catching the issued <i>E_NOTICE</i>. </p> </div> </div> <div class="refsect1 seealso"> <h3 class="title">See Also</h3> <p class="para"> <ul class="simplelist"> <li class="member"><a href="function.serialize.html" class="function" rel="rdfs-seeAlso">serialize()</a></li> </ul> </p> </div></div><hr /><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.strval.html">strval</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.unset.html">unset</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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