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<div class="refnamediv">
<h1 class="refname">trim</h1>
<p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">trim</span> — <span class="dc-title">Strip whitespace (or other characters) from the beginning and end of a string</span></p>
</div>
<div class="refsect1 description" id="refsect1-function.trim-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="type">string</span> <span class="methodname"><strong>trim</strong></span>
( <span class="methodparam"><span class="type">string</span> <code class="parameter">$str</code></span>
[, <span class="methodparam"><span class="type">string</span> <code class="parameter">$charlist</code><span class="initializer"> = " \t\n\r\0\x0B"</span></span>
] )</div>
<p class="para rdfs-comment">
This function returns a string with whitespace stripped from the
beginning and end of <em><code class="parameter">str</code></em>.
Without the second parameter,
<span class="function"><strong>trim()</strong></span> will strip these characters:
<ul class="itemizedlist">
<li class="listitem">
<span class="simpara">
" " (<acronym title="American Standard Code for Information Interchange">ASCII</acronym> <em>32</em>
(<em>0x20</em>)), an ordinary space.
</span>
</li>
<li class="listitem">
<span class="simpara">
"\t" (<acronym title="American Standard Code for Information Interchange">ASCII</acronym> <em>9</em>
(<em>0x09</em>)), a tab.
</span>
</li>
<li class="listitem">
<span class="simpara">
"\n" (<acronym title="American Standard Code for Information Interchange">ASCII</acronym> <em>10</em>
(<em>0x0A</em>)), a new line (line feed).
</span>
</li>
<li class="listitem">
<span class="simpara">
"\r" (<acronym title="American Standard Code for Information Interchange">ASCII</acronym> <em>13</em>
(<em>0x0D</em>)), a carriage return.
</span>
</li>
<li class="listitem">
<span class="simpara">
"\0" (<acronym title="American Standard Code for Information Interchange">ASCII</acronym> <em>0</em>
(<em>0x00</em>)), the <em>NUL</em>-byte.
</span>
</li>
<li class="listitem">
<span class="simpara">
"\x0B" (<acronym title="American Standard Code for Information Interchange">ASCII</acronym> <em>11</em>
(<em>0x0B</em>)), a vertical tab.
</span>
</li>
</ul>
</p>
</div>
<div class="refsect1 parameters" id="refsect1-function.trim-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<span class="term"><em><code class="parameter">str</code></em></span>
<dd>
<p class="para">
The <span class="type"><a href="language.types.string.html" class="type string">string</a></span> that will be trimmed.
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">charlist</code></em></span>
<dd>
<p class="para">
Optionally, the stripped characters can also be specified using
the <em><code class="parameter">charlist</code></em> parameter.
Simply list all characters that you want to be stripped. With
<em>..</em> you can specify a range of characters.
</p>
</dd>
</dt>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.trim-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
The trimmed string.
</p>
</div>
<div class="refsect1 changelog" id="refsect1-function.trim-changelog">
<h3 class="title">Changelog</h3>
<p class="para">
<table class="doctable informaltable">
<thead>
<tr>
<th>Version</th>
<th>Description</th>
</tr>
</thead>
<tbody class="tbody">
<tr>
<td>4.1.0</td>
<td>
The optional <em><code class="parameter">charlist</code></em> parameter was added.
</td>
</tr>
</tbody>
</table>
</p>
</div>
<div class="refsect1 examples" id="refsect1-function.trim-examples">
<h3 class="title">Examples</h3>
<p class="para">
<div class="example" id="example-4922">
<p><strong>Example #1 Usage example of <span class="function"><strong>trim()</strong></span></strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /><br />$text </span><span style="color: #007700">= </span><span style="color: #DD0000">"\t\tThese are a few words :) ... "</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$binary </span><span style="color: #007700">= </span><span style="color: #DD0000">"\x09Example string\x0A"</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$hello </span><span style="color: #007700">= </span><span style="color: #DD0000">"Hello World"</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$text</span><span style="color: #007700">, </span><span style="color: #0000BB">$binary</span><span style="color: #007700">, </span><span style="color: #0000BB">$hello</span><span style="color: #007700">);<br /><br />print </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /><br /></span><span style="color: #0000BB">$trimmed </span><span style="color: #007700">= </span><span style="color: #0000BB">trim</span><span style="color: #007700">(</span><span style="color: #0000BB">$text</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$trimmed</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">$trimmed </span><span style="color: #007700">= </span><span style="color: #0000BB">trim</span><span style="color: #007700">(</span><span style="color: #0000BB">$text</span><span style="color: #007700">, </span><span style="color: #DD0000">" \t."</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$trimmed</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">$trimmed </span><span style="color: #007700">= </span><span style="color: #0000BB">trim</span><span style="color: #007700">(</span><span style="color: #0000BB">$hello</span><span style="color: #007700">, </span><span style="color: #DD0000">"Hdle"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$trimmed</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">$trimmed </span><span style="color: #007700">= </span><span style="color: #0000BB">trim</span><span style="color: #007700">(</span><span style="color: #0000BB">$hello</span><span style="color: #007700">, </span><span style="color: #DD0000">'HdWr'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$trimmed</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// trim the ASCII control characters at the beginning and end of $binary<br />// (from 0 to 31 inclusive)<br /></span><span style="color: #0000BB">$clean </span><span style="color: #007700">= </span><span style="color: #0000BB">trim</span><span style="color: #007700">(</span><span style="color: #0000BB">$binary</span><span style="color: #007700">, </span><span style="color: #DD0000">"\x00..\x1F"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$clean</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 screen">
<div class="cdata"><pre>
string(32) " These are a few words :) ... "
string(16) " Example string
"
string(11) "Hello World"
string(28) "These are a few words :) ..."
string(24) "These are a few words :)"
string(5) "o Wor"
string(9) "ello Worl"
string(14) "Example string"
</pre></div>
</div>
</div>
</p>
<p class="para">
<div class="example" id="example-4923">
<p><strong>Example #2 Trimming array values with <span class="function"><strong>trim()</strong></span></strong></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">trim_value</span><span style="color: #007700">(&</span><span style="color: #0000BB">$value</span><span style="color: #007700">) <br />{ <br /> </span><span style="color: #0000BB">$value </span><span style="color: #007700">= </span><span style="color: #0000BB">trim</span><span style="color: #007700">(</span><span style="color: #0000BB">$value</span><span style="color: #007700">); <br />}<br /><br /></span><span style="color: #0000BB">$fruit </span><span style="color: #007700">= array(</span><span style="color: #DD0000">'apple'</span><span style="color: #007700">,</span><span style="color: #DD0000">'banana '</span><span style="color: #007700">, </span><span style="color: #DD0000">' cranberry '</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$fruit</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">array_walk</span><span style="color: #007700">(</span><span style="color: #0000BB">$fruit</span><span style="color: #007700">, </span><span style="color: #DD0000">'trim_value'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$fruit</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 screen">
<div class="cdata"><pre>
array(3) {
[0]=>
string(5) "apple"
[1]=>
string(7) "banana "
[2]=>
string(11) " cranberry "
}
array(3) {
[0]=>
string(5) "apple"
[1]=>
string(6) "banana"
[2]=>
string(9) "cranberry"
}
</pre></div>
</div>
</div>
</p>
</div>
<div class="refsect1 notes" id="refsect1-function.trim-notes">
<h3 class="title">Notes</h3>
<blockquote class="note"><p><strong class="note">Note</strong>:
<strong>Possible gotcha: removing middle characters</strong><br />
<p class="para">
Because <span class="function"><strong>trim()</strong></span> trims characters from the beginning and end of
a <span class="type"><a href="language.types.string.html" class="type string">string</a></span>, it may be confusing when characters are (or are not) removed from
the middle. <em>trim('abc', 'bad')</em> removes both 'a' and 'b' because it
trims 'a' thus moving 'b' to the beginning to also be trimmed. So, this is why it "works"
whereas <em>trim('abc', 'b')</em> seemingly does not.
</p>
</p></blockquote>
</div>
<div class="refsect1 seealso" id="refsect1-function.trim-seealso">
<h3 class="title">See Also</h3>
<p class="para">
<ul class="simplelist">
<li class="member"> <span class="function"><a href="function.ltrim.html" class="function" rel="rdfs-seeAlso">ltrim()</a> - Strip whitespace (or other characters) from the beginning of a string</span></li>
<li class="member"> <span class="function"><a href="function.rtrim.html" class="function" rel="rdfs-seeAlso">rtrim()</a> - Strip whitespace (or other characters) from the end of a string</span></li>
<li class="member"> <span class="function"><a href="function.str-replace.html" class="function" rel="rdfs-seeAlso">str_replace()</a> - Replace all occurrences of the search string with the replacement string</span></li>
</ul>
</p>
</div>
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