path: root/docs/en/cowboy/2.6/manual/cowboy_req.has_resp_header/index.html



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<h1 class="lined-header"><span>cowboy_req:has_resp_header(3)</span></h1>

<h2 id="_name">Name</h2>
<p>cowboy_req:has_resp_header - Is the given response header set?</p>
<h2 id="_description">Description</h2>
<div class="listingblock"><div class="content"><!-- Generator: GNU source-highlight 3.1.8
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><b><font color="#000000">has_resp_header</font></b>(<font color="#009900">Name</font>, <font color="#009900">Req</font> <font color="#990000">::</font> <b><font color="#000000">cowboy_req:req</font></b>()) <font color="#990000">-&gt;</font> <b><font color="#000000">boolean</font></b>()

<font color="#009900">Name</font> <font color="#990000">::</font> <b><font color="#000080">binary</font></b>()  <i><font color="#9A1900">%% lowercase; case insensitive</font></i></tt></pre>
</div></div>
<p>Return whether the given response header has been set.</p>
<p>The header name must be given as a lowercase binary string. While header names are case insensitive, Cowboy requires them to be given as lowercase to function properly.</p>
<h2 id="_arguments">Arguments</h2>
<dl><dt>Name</dt>
<dd><p>Header name as a lowercase binary string.</p>
</dd>
<dt>Req</dt>
<dd><p>The Req object.</p>
</dd>
</dl>
<h2 id="_return_value">Return value</h2>
<p>A boolean indicating whether the given response header has been set.</p>
<h2 id="_changelog">Changelog</h2>
<ul><li><strong>1.0</strong>: Function introduced.
</li>
</ul>
<h2 id="_examples">Examples</h2>
<div class="listingblock"><div class="title">Check whether the content-type header has been set</div>
<div class="content"><!-- Generator: GNU source-highlight 3.1.8
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><font color="#000080">false</font> <font color="#990000">=</font> <b><font color="#000000">cowboy_req:has_resp_header</font></b>(<font color="#990000">&lt;&lt;</font><font color="#FF0000">"content-type"</font><font color="#990000">&gt;&gt;</font>, <font color="#009900">Req0</font>),
<font color="#009900">Req</font> <font color="#990000">=</font> <b><font color="#000000">cowboy_req:set_resp_header</font></b>(<font color="#990000">&lt;&lt;</font><font color="#FF0000">"content-type"</font><font color="#990000">&gt;&gt;</font>, <font color="#990000">&lt;&lt;</font><font color="#FF0000">"text/html"</font><font color="#990000">&gt;&gt;</font>, <font color="#009900">Req0</font>),
<font color="#000080">true</font> <font color="#990000">=</font> <b><font color="#000000">cowboy_req:has_resp_header</font></b>(<font color="#990000">&lt;&lt;</font><font color="#FF0000">"content-type"</font><font color="#990000">&gt;&gt;</font>, <font color="#009900">Req</font>)<font color="#990000">.</font></tt></pre>
</div></div>
<h2 id="_see_also">See also</h2>
<p><a href="../cowboy_req">cowboy_req(3)</a>, <a href="../cowboy_req.set_resp_header">cowboy_req:set_resp_header(3)</a>, <a href="../cowboy_req.set_resp_headers">cowboy_req:set_resp_headers(3)</a>, <a href="../cowboy_req.resp_header">cowboy_req:resp_header(3)</a>, <a href="../cowboy_req.resp_headers">cowboy_req:resp_headers(3)</a>, <a href="../cowboy_req.delete_resp_header">cowboy_req:delete_resp_header(3)</a></p>


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<h1 class="lined-header"><span>cowboy_req:has_resp_header(3)</span></h1>

<h2 id="_name">Name</h2>
<p>cowboy_req:has_resp_header - Is the given response header set?</p>
<h2 id="_description">Description</h2>
<div class="listingblock"><div class="content"><!-- Generator: GNU source-highlight 3.1.8
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><b><font color="#000000">has_resp_header</font></b>(<font color="#009900">Name</font>, <font color="#009900">Req</font> <font color="#990000">::</font> <b><font color="#000000">cowboy_req:req</font></b>()) <font color="#990000">-&gt;</font> <b><font color="#000000">boolean</font></b>()

<font color="#009900">Name</font> <font color="#990000">::</font> <b><font color="#000080">binary</font></b>()  <i><font color="#9A1900">%% lowercase; case insensitive</font></i></tt></pre>
</div></div>
<p>Return whether the given response header has been set.</p>
<p>The header name must be given as a lowercase binary string. While header names are case insensitive, Cowboy requires them to be given as lowercase to function properly.</p>
<h2 id="_arguments">Arguments</h2>
<dl><dt>Name</dt>
<dd><p>Header name as a lowercase binary string.</p>
</dd>
<dt>Req</dt>
<dd><p>The Req object.</p>
</dd>
</dl>
<h2 id="_return_value">Return value</h2>
<p>A boolean indicating whether the given response header has been set.</p>
<h2 id="_changelog">Changelog</h2>
<ul><li><strong>1.0</strong>: Function introduced.
</li>
</ul>
<h2 id="_examples">Examples</h2>
<div class="listingblock"><div class="title">Check whether the content-type header has been set</div>
<div class="content"><!-- Generator: GNU source-highlight 3.1.8
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><font color="#000080">false</font> <font color="#990000">=</font> <b><font color="#000000">cowboy_req:has_resp_header</font></b>(<font color="#990000">&lt;&lt;</font><font color="#FF0000">"content-type"</font><font color="#990000">&gt;&gt;</font>, <font color="#009900">Req0</font>),
<font color="#009900">Req</font> <font color="#990000">=</font> <b><font color="#000000">cowboy_req:set_resp_header</font></b>(<font color="#990000">&lt;&lt;</font><font color="#FF0000">"content-type"</font><font color="#990000">&gt;&gt;</font>, <font color="#990000">&lt;&lt;</font><font color="#FF0000">"text/html"</font><font color="#990000">&gt;&gt;</font>, <font color="#009900">Req0</font>),
<font color="#000080">true</font> <font color="#990000">=</font> <b><font color="#000000">cowboy_req:has_resp_header</font></b>(<font color="#990000">&lt;&lt;</font><font color="#FF0000">"content-type"</font><font color="#990000">&gt;&gt;</font>, <font color="#009900">Req</font>)<font color="#990000">.</font></tt></pre>
</div></div>
<h2 id="_see_also">See also</h2>
<p><a href="../cowboy_req">cowboy_req(3)</a>, <a href="../cowboy_req.set_resp_header">cowboy_req:set_resp_header(3)</a>, <a href="../cowboy_req.set_resp_headers">cowboy_req:set_resp_headers(3)</a>, <a href="../cowboy_req.resp_header">cowboy_req:resp_header(3)</a>, <a href="../cowboy_req.resp_headers">cowboy_req:resp_headers(3)</a>, <a href="../cowboy_req.delete_resp_header">cowboy_req:delete_resp_header(3)</a></p>


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