我正在尝试制作一个简单的 UDP 套接字类来在 C++ 程序和 Java 程序之间进行一些对话，所以我正在尝试制作一个处理所有 UDP 传输的套接字类，但我无法让程序编译，因为我收到大约 8 个 lnk2019 错误，我什至不知道它们是什么意思。我主要在 Java 中工作，只有在我不得不大声笑时才使用 c++。我有 3 个文件，套接字头和代码。此外，Udp 套接字代码来自 rFactor-Nesim，因此套接字代码不是我编写的。

UdpSocket.cpp

#include "UdpSocket.hpp"

#include <stdio.h>

UdpSocket::UdpSocket(const char* host, int port) 
: mHost(host), mPort(port)
{
}

UdpSocket::~UdpSocket(void)
{
}

void UdpSocket::Open()
{
if(WSAStartup(MAKEWORD(2, 0), &mWinsockData) != 0)
    fprintf(stderr, "WSAStartup() failed");   

if ((mSocket = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
    perror("socket() failed");   

memset(&mSocketAddress, 0, sizeof(mSocketAddress));
mSocketAddress.sin_family = AF_INET;
mSocketAddress.sin_addr.s_addr = inet_addr(mHost);
mSocketAddress.sin_port = htons(mPort);
}

void UdpSocket::Close()
{
closesocket(mSocket);  
WSACleanup();
}

void UdpSocket::Send(char* str, size_t length)
{
size_t result = sendto(mSocket, str, length, 0, 
    (struct sockaddr *) &mSocketAddress, sizeof(mSocketAddress));

if(result != length)
    perror("sendto() sent incorrect number of bytes");   
}

UdpSocket.hpp

#ifndef UDPSOCKET_HPP
#define UDPSOCKET_HPP

#include <WinSock.h>

class UdpSocket
{
public:
UdpSocket(const char* host, int port);
~UdpSocket(void);

void Send(char* str, size_t length);

void Open();
void Close();
private:
const char* mHost;
int mPort;
int mSocket;
struct sockaddr_in mSocketAddress;
WSADATA mWinsockData;
};

#endif // UDPSOCKET_HPP

和主要

#include "Socket/UdpSocket.hpp"
#include <iostream>


int Main(){
UdpSocket* testSocket = new UdpSocket("127.0.0.1", 27469);
testSocket->Open();
system("pause");
return 0;
}

任何帮助都会很棒。我对c++不是很了解，但我做了一点

控制台输出:

Error   1   error LNK2019: unresolved external symbol __imp__htons@4 referenced in function "public: void __thiscall UdpSocket::Open(void)" (?Open@UdpSocket@@QAEXXZ)   UdpSocket.obj   SocketTest
Error   2   error LNK2019: unresolved external symbol __imp__inet_addr@4 referenced in function "public: void __thiscall UdpSocket::Open(void)" (?Open@UdpSocket@@QAEXXZ)   UdpSocket.obj   SocketTest
Error   3   error LNK2019: unresolved external symbol __imp__socket@12 referenced in function "public: void __thiscall UdpSocket::Open(void)" (?Open@UdpSocket@@QAEXXZ) UdpSocket.obj   SocketTest
Error   4   error LNK2019: unresolved external symbol __imp__WSAStartup@8 referenced in function "public: void __thiscall UdpSocket::Open(void)" (?Open@UdpSocket@@QAEXXZ)  UdpSocket.obj   SocketTest
Error   5   error LNK2019: unresolved external symbol __imp__WSACleanup@0 referenced in function "public: void __thiscall UdpSocket::Close(void)" (?Close@UdpSocket@@QAEXXZ)    UdpSocket.obj   SocketTest
Error   6   error LNK2019: unresolved external symbol __imp__closesocket@4 referenced in function "public: void __thiscall UdpSocket::Close(void)" (?Close@UdpSocket@@QAEXXZ)   UdpSocket.obj   SocketTest
Error   7   error LNK2019: unresolved external symbol __imp__sendto@24 referenced in function "public: void __thiscall UdpSocket::Send(char *,unsigned int)" (?Send@UdpSocket@@QAEXPADI@Z)  UdpSocket.obj   SocketTest
Error   8   error LNK2019: unresolved external symbol _main referenced in function ___tmainCRTStartup   MSVCRTD.lib SocketTest
Error   9   fatal error LNK1120: 8 unresolved externals C:\Users\Brendan\Documents\Visual Studio 2008\Projects\SocketTest\Debug\SocketTest.exe  SocketTest

最佳答案

听起来您无法链接到 Winsock - Ws2_32.lib

如果您从命令行构建，请将 Ws2_32.lib 添加到您的 link 命令行。

如果您是从 Visual Studio 构建的，请在项目配置对话框中查找链接器标志/设置。

关于c++ - lnk2019 visual studio错误，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/15062654/