IteratorConnectHandler.html
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<div class="titlepage"><div><div><h3 class="title">
<a name="asio.reference.IteratorConnectHandler"></a><a class="link" href="IteratorConnectHandler.html" title="Iterator connect handler requirements">Iterator connect
handler requirements</a>
</h3></div></div></div>
<p>
An iterator connect handler must meet the requirements for a <a class="link" href="Handler.html" title="Handlers">handler</a>.
A value <code class="computeroutput">h</code> of an iterator connect handler class should work correctly
in the expression <code class="computeroutput">h(ec, i)</code>, where <code class="computeroutput">ec</code> is an lvalue
of type <code class="computeroutput">const error_code</code> and <code class="computeroutput">i</code> is an lvalue of
the type <code class="computeroutput">Iterator</code> used in the corresponding <code class="computeroutput">connect()</code>
or async_connect()` function.
</p>
<h5>
<a name="asio.reference.IteratorConnectHandler.h0"></a>
<span><a name="asio.reference.IteratorConnectHandler.examples"></a></span><a class="link" href="IteratorConnectHandler.html#asio.reference.IteratorConnectHandler.examples">Examples</a>
</h5>
<p>
A free function as an iterator connect handler:
</p>
<pre class="programlisting">void connect_handler(
const asio::error_code& ec,
asio::ip::tcp::resolver::iterator iterator)
{
...
}
</pre>
<p>
An iterator connect handler function object:
</p>
<pre class="programlisting">struct connect_handler
{
...
template <typename Iterator>
void operator()(
const asio::error_code& ec,
Iterator iterator)
{
...
}
...
};
</pre>
<p>
A lambda as an iterator connect handler:
</p>
<pre class="programlisting">asio::async_connect(...,
[](const asio::error_code& ec,
asio::ip::tcp::resolver::iterator iterator)
{
...
});
</pre>
<p>
A non-static class member function adapted to an iterator connect handler
using <code class="computeroutput">std::bind()</code>:
</p>
<pre class="programlisting">void my_class::connect_handler(
const asio::error_code& ec,
asio::ip::tcp::resolver::iterator iterator)
{
...
}
...
asio::async_connect(...,
std::bind(&my_class::connect_handler,
this, std::placeholders::_1,
std::placeholders::_2));
</pre>
<p>
A non-static class member function adapted to an iterator connect handler
using <code class="computeroutput">boost::bind()</code>:
</p>
<pre class="programlisting">void my_class::connect_handler(
const asio::error_code& ec,
asio::ip::tcp::resolver::iterator iterator)
{
...
}
...
asio::async_connect(...,
boost::bind(&my_class::connect_handler,
this, asio::placeholders::error,
asio::placeholders::iterator));
</pre>
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<td align="right"><div class="copyright-footer">Copyright © 2003-2020 Christopher M.
Kohlhoff<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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