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<title>Returns the difference between two DateTime objects</title>
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</div><hr /><div id="datetime.diff" class="refentry">
<div class="refnamediv">
<h1 class="refname">DateTime::diff</h1>
<h1 class="refname">DateTimeImmutable::diff</h1>
<h1 class="refname">DateTimeInterface::diff</h1>
<h1 class="refname">date_diff</h1>
<p class="verinfo">(PHP 5 >= 5.3.0)</p><p class="refpurpose"><span class="refname">DateTime::diff</span> -- <span class="refname">DateTimeImmutable::diff</span> -- <span class="refname">DateTimeInterface::diff</span> -- <span class="refname">date_diff</span> — <span class="dc-title">Returns the difference between two DateTime objects</span></p>
</div>
<div class="refsect1 description" id="refsect1-datetime.diff-description">
<h3 class="title">Description</h3>
<p class="para">Object oriented style</p>
<div class="methodsynopsis dc-description">
<span class="modifier">public</span> <span class="type"><a href="class.dateinterval.html" class="type DateInterval">DateInterval</a></span> <span class="methodname"><strong>DateTime::diff</strong></span>
( <span class="methodparam"><span class="type"><a href="class.datetimeinterface.html" class="type DateTimeInterface">DateTimeInterface</a></span> <code class="parameter">$datetime2</code></span>
[, <span class="methodparam"><span class="type">bool</span> <code class="parameter">$absolute</code><span class="initializer"> = false</span></span>
] )</div>
<div class="methodsynopsis dc-description">
<span class="modifier">public</span> <span class="type"><a href="class.dateinterval.html" class="type DateInterval">DateInterval</a></span> <span class="methodname"><strong>DateTimeImmutable::diff</strong></span>
( <span class="methodparam"><span class="type"><a href="class.datetimeinterface.html" class="type DateTimeInterface">DateTimeInterface</a></span> <code class="parameter">$datetime2</code></span>
[, <span class="methodparam"><span class="type">bool</span> <code class="parameter">$absolute</code><span class="initializer"> = false</span></span>
] )</div>
<div class="methodsynopsis dc-description">
<span class="modifier">public</span> <span class="type"><a href="class.dateinterval.html" class="type DateInterval">DateInterval</a></span> <span class="methodname"><strong>DateTimeInterface::diff</strong></span>
( <span class="methodparam"><span class="type"><a href="class.datetimeinterface.html" class="type DateTimeInterface">DateTimeInterface</a></span> <code class="parameter">$datetime2</code></span>
[, <span class="methodparam"><span class="type">bool</span> <code class="parameter">$absolute</code><span class="initializer"> = false</span></span>
] )</div>
<p class="para rdfs-comment">Procedural style</p>
<div class="methodsynopsis dc-description">
<span class="type"><a href="class.dateinterval.html" class="type DateInterval">DateInterval</a></span> <span class="methodname"><a href="function.date-diff.html" class="methodname">date_diff</a></span>
( <span class="methodparam"><span class="type"><a href="class.datetimeinterface.html" class="type DateTimeInterface">DateTimeInterface</a></span> <code class="parameter">$datetime1</code></span>
, <span class="methodparam"><span class="type"><a href="class.datetimeinterface.html" class="type DateTimeInterface">DateTimeInterface</a></span> <code class="parameter">$datetime2</code></span>
[, <span class="methodparam"><span class="type">bool</span> <code class="parameter">$absolute</code><span class="initializer"> = false</span></span>
] )</div>
<p class="para rdfs-comment">
Returns the difference between two <a href="class.datetimeinterface.html" class="classname">DateTimeInterface</a>
objects.
</p>
</div>
<div class="refsect1 parameters" id="refsect1-datetime.diff-parameters">
<h3 class="title">Parameters</h3>
<dl>
<dt>
<span class="term"><em><code class="parameter">datetime</code></em></span>
<dd>
<p class="para">
The date to compare to.
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">absolute</code></em></span>
<dd>
<p class="para">
Should the interval be forced to be positive?
</p>
</dd>
</dt>
</dl>
</div>
<div class="refsect1 returnvalues" id="refsect1-datetime.diff-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
The <a href="class.dateinterval.html" class="classname">DateInterval</a> object representing the
difference between the two dates or <strong><code>FALSE</code></strong> on failure.
</p>
</div>
<div class="refsect1 examples" id="refsect1-datetime.diff-examples">
<h3 class="title">Examples</h3>
<div class="example" id="example-2273">
<p><strong>Example #1 <span class="function"><strong>DateTime::diff()</strong></span> example</strong></p>
<div class="example-contents"><p>Object oriented style</p></div>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br />$datetime1 </span><span style="color: #007700">= new </span><span style="color: #0000BB">DateTime</span><span style="color: #007700">(</span><span style="color: #DD0000">'2009-10-11'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$datetime2 </span><span style="color: #007700">= new </span><span style="color: #0000BB">DateTime</span><span style="color: #007700">(</span><span style="color: #DD0000">'2009-10-13'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$interval </span><span style="color: #007700">= </span><span style="color: #0000BB">$datetime1</span><span style="color: #007700">-></span><span style="color: #0000BB">diff</span><span style="color: #007700">(</span><span style="color: #0000BB">$datetime2</span><span style="color: #007700">);<br />echo </span><span style="color: #0000BB">$interval</span><span style="color: #007700">-></span><span style="color: #0000BB">format</span><span style="color: #007700">(</span><span style="color: #DD0000">'%R%a days'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
<div class="example-contents"><p>Procedural style</p></div>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br />$datetime1 </span><span style="color: #007700">= </span><span style="color: #0000BB">date_create</span><span style="color: #007700">(</span><span style="color: #DD0000">'2009-10-11'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$datetime2 </span><span style="color: #007700">= </span><span style="color: #0000BB">date_create</span><span style="color: #007700">(</span><span style="color: #DD0000">'2009-10-13'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$interval </span><span style="color: #007700">= </span><span style="color: #0000BB">date_diff</span><span style="color: #007700">(</span><span style="color: #0000BB">$datetime1</span><span style="color: #007700">, </span><span style="color: #0000BB">$datetime2</span><span style="color: #007700">);<br />echo </span><span style="color: #0000BB">$interval</span><span style="color: #007700">-></span><span style="color: #0000BB">format</span><span style="color: #007700">(</span><span style="color: #DD0000">'%R%a days'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
<div class="example-contents"><p>The above examples will output:</p></div>
<div class="example-contents screen">
<div class="cdata"><pre>
+2 days
</pre></div>
</div>
</div>
<div class="example" id="example-2274">
<p><strong>Example #2 <a href="class.datetime.html" class="classname">DateTime</a> object comparison</strong></p>
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">
As of PHP 5.2.2, DateTime objects can be compared using
<a href="language.operators.comparison.html" class="link">comparison operators</a>.
</p>
</p></blockquote>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br />$date1 </span><span style="color: #007700">= new </span><span style="color: #0000BB">DateTime</span><span style="color: #007700">(</span><span style="color: #DD0000">"now"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$date2 </span><span style="color: #007700">= new </span><span style="color: #0000BB">DateTime</span><span style="color: #007700">(</span><span style="color: #DD0000">"tomorrow"</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$date1 </span><span style="color: #007700">== </span><span style="color: #0000BB">$date2</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$date1 </span><span style="color: #007700">< </span><span style="color: #0000BB">$date2</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$date1 </span><span style="color: #007700">> </span><span style="color: #0000BB">$date2</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 screen">
<div class="cdata"><pre>
bool(false)
bool(true)
bool(false)
</pre></div>
</div>
</div>
</div>
<div class="refsect1 seealso" id="refsect1-datetime.diff-seealso">
<h3 class="title">See Also</h3>
<ul class="simplelist">
<li class="member"> <span class="function"><a href="dateinterval.format.html" class="function" rel="rdfs-seeAlso">DateInterval::format()</a> - Formats the interval</span></li>
<li class="member"> <span class="function"><a href="datetime.add.html" class="function" rel="rdfs-seeAlso">DateTime::add()</a> - Adds an amount of days, months, years, hours, minutes and seconds to a
DateTime object</span></li>
<li class="member"> <span class="function"><a href="datetime.sub.html" class="function" rel="rdfs-seeAlso">DateTime::sub()</a> - Subtracts an amount of days, months, years, hours, minutes and seconds from
a DateTime object</span></li>
</ul>
</div>
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