Bind resolve_handler to resolver async_resolve using boost::asio
I have this code. How can I bind my method resolve_handler with the expected iterator and error parameters? Is it the correct way to break down the connection logic?
void FileClient::start()
{
try {
boost::asio::ip::tcp::resolver::query query("ip", "port");
resolver_.async_resolve(query, boost::bind(
&FileClient::resolve_handler, this
));
}
catch (std::exception& e)
{
std::cerr << "Exception: " << e.what() << "\n";
}
}
void FileClient::resolve开发者_JAVA百科_handler(const boost::system::error_code &_error,
boost::asio::ip::tcp::resolver::iterator _it)
{
if (!_error)
socket_.async_connect(*_it, boost::bind(
&FileClient::connect_handler, this, boost::asio::placeholders::error
));
else
std::cerr << "resolve_handler error: " << _error << std::endl;
}
There are examples in boost.asio tutorials, for example, from this HTTP async client
tcp::resolver::query query(server, "http");
resolver_.async_resolve(query,
boost::bind(&client::handle_resolve, this,
boost::asio::placeholders::error,
boost::asio::placeholders::iterator));
...
void handle_resolve(const boost::system::error_code& err,
tcp::resolver::iterator endpoint_iterator)
{
if (!err)
{
// Attempt a connection to the first endpoint in the list. Each endpoint
// will be tried until we successfully establish a connection.
tcp::endpoint endpoint = *endpoint_iterator;
socket_.async_connect(endpoint,
boost::bind(&client::handle_connect, this,
boost::asio::placeholders::error, ++endpoint_iterator));
}
else
{
std::cout << "Error: " << err.message() << "\n";
}
}
(their handle_connect
continues to increment endpoint_iterator
as necessary)
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