如何在MetaTrader4终端中获取当前毫秒？

Question

如何使用专家顾问从MQL4获取当前毫秒。

也就是说:在Java中，我们可以使用system.currenttimemillis()获得当前毫秒

Answer 1

MT4的“获得毫秒”问题已经存在了很长时间。这是我为解决这个问题而设计的一个黑客。

//+------------------------------------------------------------------+
//|                                                     timeInMs.mq4 |
//|                                       Copyright 2017, Joseph Lee |
//+------------------------------------------------------------------+
#property copyright "Copyright 2017, Joseph Lee"
#property link      "https://www.facebook.com/joseph.fhlee"
#property version   "1.00"
#property strict

int     prevSecondTime      = 0;
uint    prevSecondTick      = 0;


int OnInit()    {
    // Create an Event that triggers every 1 millisecond.
    // **NOTE: GetTickCount() is accurate to 16ms only, so
    // in practice, no need to trigger every 1ms.
    EventSetMillisecondTimer(1);
    return(INIT_SUCCEEDED);
}

void OnTick() {
    Comment( "Now: " + TimeLocal() + " :: " + getCurrentMs() + " ms. +- 16ms accuracy.");
}

int getCurrentMs() {
    return(GetTickCount() - prevSecondTick);
}

// This is an EVENT function that will be called every
// x milliseconds [see EventSetMillisecondTimer() in OnInit()]
void OnTimer() {
    // If a new "second" occurs, record GetTickCount()
    if(TimeLocal() > prevSecondTime) {
        prevSecondTick  = GetTickCount();
        prevSecondTime  = TimeLocal();
    }
}

Answer 2

可能有亲戚ms甚至我们

要小心，因为两者都是相对的，但是一个是关于系统启动的，另一个是关于MQL4代码执行单元启动的。

uint GetTickCount();函数返回自系统启动以来经过的的毫秒数。计数器受系统计时器的限制。时间是以无符号整数的形式存储的，因此，如果计算机不间断地工作，那么每隔49.7天时间就会被过度填充。

GetMicrosecondCount()函数返回自MQL程序启动以来经过的的微秒数。ulong GetMicrosecondCount();

可以有绝对毫秒，甚至我们，与康斯特(！)绝对错误，

这将显示出在精确测量时间时既没有任何漂移，也没有抖动。。

这不是很好的外汇领域，毫秒是“充满事件”的和微秒(在最近的专业级设计纳秒)重要吗?！

// -----------------------------------------------------------------
ulong system_currenttimemillis(){
      return(   OnStart_GLOB_MILLISECONDS       // ABS [ms] SYNC-ed OnStart() WITH [s]-EDGE-ALIGNMENT
            + (           GetMicrosecondCount() // + DELTA ------------------
              - OnStart_BASE_MICROSECONDS       //   since SYNC-ing OnStart()
                ) / 1000 // =================== //   DELTA [ms] =============
              );
}
// -----------------------------------------------------------------
static ulong    OnStart_GLOB_MICROSECONDS;
static ulong    OnStart_GLOB_MILLISECONDS;
static ulong    OnStart_EoDY_MICROSECONDS;
static datetime OnStart_EoDY_DATETIME;
static datetime OnStart_BASE_DATETIME;
static uint     OnStart_BASE_MILLISECONDS;
static ulong    OnStart_BASE_MICROSECONDS;
// -----------------------------------------------------------------
void            OnStart(){ /* { SCRIPT | EXPERT ADVISOR | CUSTOM INDICATOR } CALL
                                                                             THIS */
                OnStart_BASE_DATETIME      = TimeLocal();           // .SET int == the number of seconds elapsed since January 01, 1970.
         while( OnStart_BASE_DATETIME     == TimeLocal() ){ // ---- // EDGE-ALIGNMENT -------------------------------------------------------
                OnStart_BASE_MICROSECONDS  = GetMicrosecondCount(); //      .SET ulong, since MQL4 program launch
                OnStart_BASE_MILLISECONDS  = GetTickCount();        //      .SET uint,  since system start
         } // ==[ MAX 1 SECOND ]=============================== NOW // EDGE-ALIGNED TO [s] ==================================================
                OnStart_BASE_DATETIME      = TimeLocal();           // .SET date and time as the number of seconds elapsed since January 01, 1970.
                OnStart_GLOB_MICROSECONDS  = (       (ulong) OnStart_BASE_DATETIME ) * 1000000;
                OnStart_GLOB_MILLISECONDS  = (       (ulong) OnStart_BASE_DATETIME ) * 1000;
                OnStart_EoDY_DATETIME      =                 OnStart_BASE_DATETIME
                                           - (               OnStart_BASE_DATETIME % 86400 );
                OnStart_EoDY_MICROSECONDS  = (   TimeSecond( OnStart_BASE_DATETIME )
                                             + ( TimeMinute( OnStart_BASE_DATETIME )
                                               + TimeHour(   OnStart_BASE_DATETIME ) * 60 ) * 60 ) * 1000000;
}
// -----------------------------------------------------------------
int OnInit()    {
    OnStart();             /*   HACK 4 { EXPERT ADVISOR | CUSTOM INDICATOR } CALL
    ...                                                                      THAT */
    ..
    return( INIT_SUCCEEDED );
}
// -----------------------------------------------------------------
ulong Get_a_Microsecond_of_a_Day(){           // THIS HAS A !!_CONSTANT_!! ONLY ABSOLUTE SYSTEMATIC TIMING ERROR
      return( (   OnStart_EoDY_MICROSECONDS   // EDGE-SYNC OnStart_EoDY + DELTA-SINCE-OnStart-SYNC-ed:
              + (           GetMicrosecondCount()                       // == NOW ( 8B ulong ) ROLL-OVER ~ 213M504 DAYS AFTER THE PROGRAM START, WAY LONGER, THAN WE WILL LIVE UNDER THE SUN
                - OnStart_BASE_MICROSECONDS   //                        //  - OnStart_BASE_MICROSECONDS
                  )
                ) // ================== // SECONDS-EDGE-SYNC-ed DISTANCE FROM EoDY-EDGE
              % 86400000000             // MODULO DAY-LENGTH ROLL-OVER
              );                        // ALL DST-MOVs TAKE PLACE OVER WEEKENDS, SO NOT DURING TRADING-HOURS, SHOULD BE JUST-ENOUGH GOOD SOLUTION :o)
}
// -----------------------------------------------------------------
uint Get_a_Millisecond_of_a_Day(){      // IMMUNE TO A uint ROLL-OVER ~ 49.7 DAYS
     return( Get_a_Microsecond_of_a_Day()
           / 1000
             );
}

• 此解决方案运行在所有{=自定义指示器}中。

Answer 3

就像这样：

ulong time = GetTickCount(); // function(); time = GetTickCount()-time;