的boost :: ASIO async_send错误

Question

使用升压下面的代码:: ASIO不会编译：

#pragma once 
#include <ctime> 
#include <iostream> 
#include <string> 
#include <stdint.h> 
#include <boost/bind.hpp> 
#include <boost/shared_ptr.hpp> 
#include <boost/enable_shared_from_this.hpp> 
#include <boost/asio.hpp> 

class Connection 
: public boost::enable_shared_from_this<Connection> 
{ 
public: 
    typedef boost::shared_ptr<Connection> pointer; 
    static pointer create(boost::asio::io_service& io_service){return pointer(new Connection(io_service));} 
    virtual ~Connection(); 
    boost::asio::ip::tcp::socket& socket(); 

    virtual void Send(uint8_t* buffer, int length); 
    void handler(const boost::system::error_code& error, std::size_t bytes_transferred); 

private: 
    explicit Connection(boost::asio::io_service& io_service); 
    boost::asio::ip::tcp::socket socket_; 
    boost::asio::ip::tcp::endpoint remote_endpoint_; 
}; 


------------------------------------------------------------------------------------------------ 
#include "Connection.h" 

Connection::Connection(boost::asio::io_service& io_service) 
    : socket_(io_service) 
    { 
    } 

Connection::~Connection() 
{ 
    //dtor 
} 


boost::asio::ip::tcp::socket& Connection::socket(){ 
    return socket_; 
} 

void Connection::Send(uint8_t* buffer, int length){ 
    socket_.async_send(boost::asio::buffer(buffer, length), 0, handler); 

} 
       // Result of operation.    // Number of bytes sent. 
void Connection::handler(const boost::system::error_code& error, std::size_t bytes_transferred){ 
    } 

这些都是该代码会产生在Visual C++中的错误：

Error 1 error C3867: 'Connection::handler': function call missing argument list; use '&Connection::handler' to create a pointer to member d:\c++\ugs\accountserver\connection.cpp 19 
Error 2 error C2780: 'void boost::asio::basic_stream_socket<Protocol>::async_send(const ConstBufferSequence &,WriteHandler)' : expects 2 arguments - 3 provided d:\c++\ugs\accountserver\connection.cpp 19 

为什么这些错误发生，我能做些什么来解决它们？

Answer 1

您对async_send通话应该是这样的：

socket_.async_send(boost::asio::buffer(buffer, length), boost::bind(&Connection::handler, this, boost::asio::placeholders::error, boost::asio::placeholders::bytes_transferred)); 

Answer 2

Error 1 error C3867: 'Connection::handler': function call missing argument list; use '&Connection::handler' to create a pointer to member d:\c++\ugs\accountserver\connection.cpp 19 

这第一个错误告诉你： 带你需要使用下面的语法的一个成员函数的“地址”：

&Connection::handler

Error 2 error C2780: 'void boost::asio::basic_stream_socket<Protocol>::async_send(const ConstBufferSequence &,WriteHandler)' : expects 2 arguments - 3 provided d:\c++\ugs\accountserver\connection.cpp 19 

第二个错误告诉你您传递给函数的参数数量不匹配

因此，调用的正确方法是

socket_.async_send(boost::asio::buffer(buffer, length), boost::bind(&Connection::handler, this, boost::asio::placeholders::error, boost::asio::placeholders::bytes_transferred));