測試規模：百萬級別

在Debug模式下，CLogStr比sprintf大概慢1倍；

但是在Release模式下，CLogStr卻快些。

log_str = "";與log_str.clear();效率差不多

// testLogString.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <stdio.h>
#include <Windows.h>
#include <__LSL_Cls_Define.h>
#include <__LogStr.h>

int main(int argc, char* argv[])
{
    int order = 978451;
    int login = 9;
    float volume = 2.0;
    double price = 145.1240;
    char* szSymbol = "EURUSD";
    char szBuf[256] = "";
    DWORD tick_beg = 0, tick_end = 0;
    __LSL_Cls::CLogStr log_str;
    int i = 0;

    tick_beg = GetTickCount();
    for(i = 0; i < 1000000; ++i)
        sprintf(szBuf, "#%d, %d buy %.2lf %s at price %.4lf successfully", order, login, volume, szSymbol, price);
    tick_end = GetTickCount();
    printf("sprintf total millseconds: %ld\r\n", tick_end - tick_beg);

    tick_beg = GetTickCount();
    for(i = 0; i < 1000000; ++i)
    {    log_str = "";//log_str.clear();
        log_str = log_str+"#"+order+", "+login+" buy "+volume+" "+szSymbol+" at price "+price+" successfully";
    //    printf("%s\n", log_str.c_str());
    //    Sleep(3000);
    }
    tick_end = GetTickCount();
    printf("log_str total millseconds: %ld\r\n", tick_end - tick_beg);
    return 0;
}

Debug模式下：

Release模式下：