单个写日志

#include <boost/log/core.hpp>
#include <boost/log/trivial.hpp>
#include <boost/log/expressions.hpp>
#include <boost/log/utility/setup/file.hpp>
#include <boost/log/utility/setup/common_attributes.hpp>
#include <boost/log/support/date_time.hpp>int main() {boost::log::add_file_log(boost::log::keywords::file_name = "example.log",boost::log::keywords::rotation_size = 10 * 1024 * 1024,boost::log::keywords::format = (boost::log::expressions::stream<< "[" << boost::log::expressions::format_date_time< boost::posix_time::ptime >("TimeStamp", "%Y-%m-%d %H:%M:%S.%f") << "]"<< "[" << boost::log::trivial::severity << "]"<< " " << boost::log::expressions::smessage));boost::log::core::get()->set_filter(boost::log::trivial::severity >= boost::log::trivial::debug);boost::log::add_common_attributes();BOOST_LOG_TRIVIAL(debug) << "Hello, Boost log!";return 0;
}

根据日志等级写日志

#include <boost/log/core.hpp>
#include <boost/log/trivial.hpp>
#include <boost/log/expressions.hpp>
#include <boost/log/utility/setup/file.hpp>
#include <boost/log/utility/setup/common_attributes.hpp>
#include <boost/log/support/date_time.hpp>int main() {// 为 info 级别日志设置接收器boost::log::add_file_log(boost::log::keywords::file_name = "info.log",boost::log::keywords::filter = boost::log::trivial::severity == boost::log::trivial::info,boost::log::keywords::format = (boost::log::expressions::stream<< "[" << boost::log::expressions::format_date_time< boost::posix_time::ptime >("TimeStamp", "%Y-%m-%d %H:%M:%S.%f") << "]"<< "[" << boost::log::trivial::severity << "]"<< " " << boost::log::expressions::smessage));// 为 error 级别日志设置接收器boost::log::add_file_log(boost::log::keywords::file_name = "error.log",boost::log::keywords::filter = boost::log::trivial::severity == boost::log::trivial::error,boost::log::keywords::format = (boost::log::expressions::stream<< "[" << boost::log::expressions::format_date_time< boost::posix_time::ptime >("TimeStamp", "%Y-%m-%d %H:%M:%S.%f") << "]"<< "[" << boost::log::trivial::severity << "]"<< " " << boost::log::expressions::smessage));boost::log::add_common_attributes();BOOST_LOG_TRIVIAL(info) << "This is an info message.";BOOST_LOG_TRIVIAL(error) << "This is an error message.";return 0;
}

自定义过滤器

#include <boost/log/core.hpp>
#include <boost/log/trivial.hpp>
#include <boost/log/expressions.hpp>
#include <boost/log/utility/setup/file.hpp>
#include <boost/log/utility/setup/common_attributes.hpp>
#include <boost/log/attributes/named_scope.hpp>
#include <boost/log/sources/record_ostream.hpp>
#include <boost/log/sources/severity_logger.hpp>namespace logging = boost::log;
namespace attrs = boost::log::attributes;
namespace src = boost::log::sources;
namespace expr = boost::log::expressions;// 自定义属性
BOOST_LOG_ATTRIBUTE_KEYWORD(module, "Module", std::string)int main() {// 为 ModuleA 设置接收器logging::add_file_log(logging::keywords::file_name = "moduleA.log",logging::keywords::filter = module == "ModuleA",logging::keywords::format = (expr::stream<< "[" << expr::format_date_time< boost::posix_time::ptime >("TimeStamp", "%Y-%m-%d %H:%M:%S.%f") << "]"<< "[" << logging::trivial::severity << "]"<< "[" << module << "]"<< " " << expr::smessage));// 为 ModuleB 设置接收器logging::add_file_log(logging::keywords::file_name = "moduleB.log",logging::keywords::filter = module == "ModuleB",logging::keywords::format = (expr::stream<< "[" << expr::format_date_time< boost::posix_time::ptime >("TimeStamp", "%Y-%m-%d %H:%M:%S.%f") << "]"<< "[" << logging::trivial::severity << "]"<< "[" << module << "]"<< " " << expr::smessage));logging::add_common_attributes();src::severity_logger<logging::trivial::severity_level> lg;auto modulea=lg.add_attribute("Module", attrs::constant<std::string>("ModuleA"));BOOST_LOG_SEV(lg, logging::trivial::info) << "This is a message from ModuleA.";lg.remove_attribute(modulea.first);lg.add_attribute("Module", attrs::constant<std::string>("ModuleB"));BOOST_LOG_SEV(lg, logging::trivial::info) << "This is a message from ModuleB.";return 0;
}