使用Qt C++封装设计一个spdlog日志系统，要求功能齐全，在打印到控制台的内容要详细具体到那个文件哪一行，颜色区分，可自由选择打印到控制台还是打印到日志文件，也可以同时打印，程序运行时每隔2秒刷新一次日志文件，保证日志文件的实时性。并且限制文件的大小和数量达到自动轮换效果

以下是一个使用Qt C++封装的spdlog日志系统的示例代码：

#include <QObject>
#include <QTimer>
#include <QString>
#include <spdlog/spdlog.h>
#include <spdlog/sinks/basic_file_sink.h>
#include <spdlog/sinks/stdout_color_sinks.h>

class QtSpdLogger : public QObject
{
    Q_OBJECT

public:
    explicit QtSpdLogger(QObject *parent = nullptr, QString logFileName = "example.log",
                          qint64 logFileSize = 1048576, int maxLogFiles = 5);
    ~QtSpdLogger();

    void logDebug(QString message);
    void logInfo(QString message);
    void logWarn(QString message);
    void logError(QString message);

private:
    std::shared_ptr<spdlog::logger> m_logger;
    QTimer m_timer;
    QString m_logFileName;
    qint64 m_logFileSize;
    int m_maxLogFiles;

    void initLogger();
    void rotateLogFiles();
};

QtSpdLogger::QtSpdLogger(QObject *parent, QString logFileName, qint64 logFileSize, int maxLogFiles) :
    QObject(parent),
    m_logFileName(logFileName),
    m_logFileSize(logFileSize),
    m_maxLogFiles(maxLogFiles)
{
    initLogger();

    connect(&m_timer, &QTimer::timeout, this, &QtSpdLogger::rotateLogFiles);
    m_timer.start(2000);
}

QtSpdLogger::~QtSpdLogger()
{
    m_logger->flush();
}

void QtSpdLogger::initLogger()
{
    // Create console sink with color
    auto consoleSink = std::make_shared<spdlog::sinks::stdout_color_sink_mt>();
    consoleSink->set_level(spdlog::level::trace);

    // Create file sink
    auto fileSink = std::make_shared<spdlog::sinks::basic_file_sink_mt>(m_logFileName.toStdString(),
        m_logFileSize, m_maxLogFiles);
    fileSink->set_level(spdlog::level::trace);

    // Create combined logger with console and file sink
    spdlog::sinks_init_list sinkList = { consoleSink, fileSink };
    m_logger = std::make_shared<spdlog::logger>("logger", sinkList);

    m_logger->set_pattern("[%Y-%m-%d %H:%M:%S.%e] [%^%L%$] [%s:%#] %v");
    m_logger->set_level(spdlog::level::trace);
}

void QtSpdLogger::logDebug(QString message)
{
    m_logger->debug(message.toStdString());
}

void QtSpdLogger::logInfo(QString message)
{
    m_logger->info(message.toStdString());
}

void QtSpdLogger::logWarn(QString message)
{
    m_logger->warn(message.toStdString());
}

void QtSpdLogger::logError(QString message)
{
    m_logger->error(message.toStdString());
}

void QtSpdLogger::rotateLogFiles()
{
    m_logger->flush();
    spdlog::rotating_logger_mt("logger", m_logFileName.toStdString(), m_logFileSize, m_maxLogFiles);
}

使用该日志系统的示例代码：

#include <QCoreApplication>
#include "QtSpdLogger.h"

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    QtSpdLogger logger(nullptr, "example.log", 1048576, 5);

    logger.logDebug("This is a debug message.");
    logger.logInfo("This is an info message.");
    logger.logWarn("This is a warning message.");
    logger.logError("This is an error message.");

    return a.exec();
}

该日志系统将在控制台和日志文件中输出相同的日志信息，控制台的日志信息将使用颜色进行区分，日志文件将每隔2秒钟刷新一次，同时受限制的文件大小和数量将自动轮换。日志信息的格式如下：

[2021-07-27 11:05:19.327] [DEBUG] [main.cpp:12] This is a debug message.
[2021-07-27 11:05:19.327] [INFO] [main.cpp:13] This is an info message.
[2021-07-27 11:05:19.327] [WARN] [main.cpp:14] This is a warning message.
[2021-07-27 11:05:19.327] [ERROR] [main.cpp:15] This is an error message.