消息

发送文本、语音、图片、位置等消息（单聊/群聊/聊天室通用，只是一个参数的差别）。

//创建消息体
    EMMessageBodyPtr body = EMTextMessageBodyPtr(new EMTextMessageBody(content.c_str()));

    CefStringUTF8 utf8(content);
    //聊天类型：单聊
    EMMessage::EMChatType type = EMMessage::SINGLE;
    if (isGoupChat.compare("groupchat") == 0)
    {
        if (roomType.compare("true") == 0)
        {
            type = EMMessage::CHATROOM;//聊天室
        }
        else
        {
            type = EMMessage::GROUP;//群聊
        }
    }
    //创建待发消息
    EMMessagePtr msg = EMMessage::createSendMessage(g_client->getLoginInfo().loginUser(), to,
        body, type);
    EMCallbackPtr msgCallback(new EMCallback(m_coh,
        [=](void)->bool
    {
        string enc = URLEncode(utf8);
        callback->Success(enc.c_str());
        return true;
    },
        [=](const easemob::EMErrorPtr)->bool
    {
        return false;
    },
        [](int){}));
    //设置消息回调
    msg->setCallback(msgCallback);
    //发送消息
    g_client->getChatManager().sendMessage(msg);

OPENFILENAME ofn;       // common dialog box structure
    TCHAR szFile[260];       // buffer for file name
    ZeroMemory(&ofn, sizeof(ofn));
    ofn.lStructSize = sizeof(ofn);
    ofn.hwndOwner = ::GetDesktopWindow();
    ofn.lpstrFile = szFile;
    ofn.lpstrFile[0] = '\0';
    ofn.nMaxFile = sizeof(szFile);
    ofn.lpstrFilter = L"所有文件(*.*)\0*.*\0\0";
    if (type.compare("img") == 0)
    {
        ofn.lpstrFilter = L"图像文件(*.bmp;*.jpg;*.png;*.gif)\0*.bmp;*.jpg;*.png;*.gif\0\0";
    }
    else if (type.compare("aud") == 0)
    {
        ofn.lpstrFilter = L"音频文件(*.mp3;*.amr;*.wmv)\0*.mp3;*.amr;*.wmv\0\0";
    }
    ofn.nFilterIndex = 1;
    ofn.lpstrFileTitle = NULL;
    ofn.nMaxFileTitle = 0;
    ofn.lpstrInitialDir = NULL;
    ofn.Flags = OFN_PATHMUSTEXIST | OFN_FILEMUSTEXIST;
    //打开系统文件对话框
    if (GetOpenFileName(&ofn) == TRUE)
    {
        //获取文件路径
        std::wstring sAttach = ofn.lpstrFile;
        CefStringUTF8 utf8(sAttach);
        //根据消息类型创建不同类型的消息体
        EMMessageBodyPtr body;
        if (type.compare("aud") == 0)
        {
            body = EMFileMessageBodyPtr(new EMFileMessageBody(utf8.ToString().c_str()));
        }
        else if (type.compare("img") == 0)
        {
            body = EMImageMessageBodyPtr(new EMImageMessageBody(utf8.ToString().c_str(), ""));
        }
        else if (type.compare("file") == 0)
        {
            body = EMFileMessageBodyPtr(new EMFileMessageBody(utf8.ToString().c_str()));
        }
        //聊天类型
        EMMessage::EMChatType chatType = EMMessage::SINGLE;
        if (isGoupChat.compare("groupchat") == 0)
        {
            if (roomType.compare("true") == 0)
            {
                chatType = EMMessage::CHATROOM;
            }
            else
            {
                chatType = EMMessage::GROUP;
            }
        }
        //创建消息
        EMMessagePtr msg = EMMessage::createSendMessage(g_client->getLoginInfo().loginUser(), to,
            body, chatType);
        EMCallbackPtr msgCallback(new EMCallback(m_coh,
            [=](void)->bool
        {
            string enc = URLEncode(utf8);
            callback->Success(enc.c_str());
            return true;
        },
            [=](const easemob::EMErrorPtr)->bool
        {
            return false;
        },
            [](int){}));
        //设置消息回调
        msg->setCallback(msgCallback);
        //发送消息
        g_client->getChatManager().sendMessage(msg);
    }

//消息监听类头文件
 
class ChatListener : public EMChatManagerListener {
public:
    ChatListener()
    {
    }

    virtual void onReceiveMessages(const EMMessageList &messages);

private:
    EMCallbackObserverHandle m_coh;
    void onTextMessage(const EMMessagePtr msg, const EMMessageBodyPtr _body, string sChatType);
    void onFileMessage(const EMMessagePtr msg, const EMMessageBodyPtr _body, string sChatType);
    void onImageMessage(const EMMessagePtr msg, const EMMessageBodyPtr _body, string sChatType);
    void onVoiceMessage(const EMMessagePtr msg, const EMMessageBodyPtr _body, string sChatType);
    void onVideoMessage(const EMMessagePtr msg, const EMMessageBodyPtr _body, string sChatType);
    void onLocationMessage(const EMMessagePtr msg, const EMMessageBodyPtr _body, string sChatType);
    string getJSHead(const EMMessagePtr msg, string sChatType, string JSFuncName);
    string getJSTail(const EMMessageBodyPtr _body, string type);
    void CallJSWithoutFilePath(string strJSHead, string strJSTail);
    void CallJSWithFilePath(string strJSHead, string strJSTail, string strPath);
};
...
...
//消息监听类实现文件

void ChatListener::onReceiveMessages(const EMMessageList &messages) 
{
    HANDLE hObject[2];
    hObject[0] = Utils::g_RosterDownloaded;
    hObject[1] = Utils::g_GroupListDownloaded;
    WaitForMultipleObjects(2, hObject, TRUE, INFINITE);


    for (EMMessagePtr msg : messages)
    {
        EMMessage::EMChatType type = msg->chatType();
        string sChatType = "chat";
        if (type == EMMessage::GROUP)
        {
            sChatType = "groupchat";
        }
        else if (type == EMMessage::CHATROOM)
        {
            sChatType = "chatroom";
        }
        const vector<EMMessageBodyPtr> &bodies = msg->bodies();
        const EMMessageBodyPtr _body = bodies[0];
        switch (_body->type())
        {
        case EMMessageBody::TEXT:
        {
            onTextMessage(msg, _body, sChatType);
            break;
        }
        case EMMessageBody::FILE:
        {
            onFileMessage(msg, _body, sChatType);
            break;
        }
        case EMMessageBody::IMAGE:
        {
            onImageMessage(msg, _body, sChatType);
            break;
        }
        case EMMessageBody::VOICE:
        {
            onVoiceMessage(msg, _body, sChatType);
            break;
        }
        case EMMessageBody::COMMAND:
            break;
        case EMMessageBody::VIDEO:
        {
            onVideoMessage(msg, _body, sChatType);
            break;
        }
        case EMMessageBody::LOCATION:
        {
            onLocationMessage(msg, _body, sChatType);
            break;
        }
        }
    }
}

void ChatListener::onTextMessage(const EMMessagePtr msg, const EMMessageBodyPtr _body, string sChatType)
{
    EMTextMessageBodyPtr body = std::dynamic_pointer_cast<EMTextMessageBody, EMMessageBody>(_body);
    std::stringstream stream;
    stream << "Demo.conn.onTextMessage('{id: \"";
    stream << msg->msgId();
    stream << "\",type : \"";
    stream << sChatType;
    stream << "\", from : \"";
    stream << msg->from();
    stream << "\",to : \"";
    stream << msg->to();
    stream << "\",data : \"";
    stream << Utils::URLEncode(body->text());
    stream << "\",ext : \"\"}');";
    Utils::CallJS(stream);
}


void ChatListener::onFileMessage(const EMMessagePtr msg, const EMMessageBodyPtr _body, string sChatType)
{
    EMFileMessageBodyPtr body = std::dynamic_pointer_cast<EMFileMessageBody, EMMessageBody>(_body);

    string strJSHead = getJSHead(msg, sChatType,"onFileMessage");
    string strJSTail = getJSTail(_body, "file");

    CallJSWithoutFilePath(strJSHead, strJSTail);

    EMCallbackPtr msgCallback(new EMCallback(m_coh,
        [=](void)->bool
    {
        if (EMFileMessageBody::SUCCESSED == body->downloadStatus())
        {
            CallJSWithFilePath(strJSHead, strJSTail, GetPathForWebPage(body->localPath()));
        }
        return true;
    },
        [=](const easemob::EMErrorPtr)->bool
    {
        return false;
    },
        [](int){}));
    msg->setCallback(msgCallback);

    g_client->getChatManager().downloadMessageAttachments(msg);
}

...
...
//注册消息监听类
ChatListener *mChatListener;
mChatListener = new ChatListener();
g_client->getChatManager().addListener(mChatListener);