使用MQL5经济日历进行交易（第六部分）：利用新闻事件分析和倒计时器实现交易入场自动化（基础篇）

class="macro">#include <Trade\Trade.mqh> class=class="str">"cmt">// Trading library for order execution
CTrade trade;              class=class="str">"cmt">// Global trade object
class=class="str">"cmt">//================== Trade Settings ==================//
class=class="str">"cmt">// Trade mode options:
enum ETradeMode {
   TRADE_BEFORE,     class=class="str">"cmt">// Trade before the news event occurs
   TRADE_AFTER,      class=class="str">"cmt">// Trade after the news event occurs
   NO_TRADE,         class=class="str">"cmt">// Do not trade
   PAUSE_TRADING     class=class="str">"cmt">// Pause trading activity(no trades until resumed)
};
input ETradeMode tradeMode       = TRADE_BEFORE; class=class="str">"cmt">// Choose the trade mode
class=class="str">"cmt">// Trade offset inputs:
input class="type">int       tradeOffsetHours   = class="num">12;         class=class="str">"cmt">// Offset hours(e.g., class="num">12 hours)
input class="type">int       tradeOffsetMinutes = class="num">5;          class=class="str">"cmt">// Offset minutes(e.g., class="num">5 minutes before)
input class="type">int       tradeOffsetSeconds = class="num">0;          class=class="str">"cmt">// Offset seconds

input class="type">class="kw">double      tradeLotSize        = class="num">0.01;      class=class="str">"cmt">// Lot size for the trade
class=class="str">"cmt">//================== Global Trade Control ==================//
class=class="str">"cmt">// Once a trade is executed for one news event, no further trades occur.
class="type">bool tradeExecuted = false;
class=class="str">"cmt">// Store the traded event’s scheduled news time for the post–trade countdown.
class="type">class="kw">datetime tradedNewsTime = class="num">0;
class=class="str">"cmt">// Global array to store event IDs that have already triggered a trade.
class="type">int triggeredNewsEvents[];

class=class="str">"cmt">//--- Function to scan for news events and execute trades based on selected criteria
class=class="str">"cmt">//--- It handles both pre-trade candidate selection and post-trade countdown updates
class="type">void CheckForNewsTrade() {
   class=class="str">"cmt">//--- Log the call to CheckForNewsTrade with the current server time
   Print("CheckForNewsTrade called at: ", TimeToString(TimeTradeServer(), TIME_SECONDS));

   class=class="str">"cmt">//--- If trading is disabled(either NO_TRADE or PAUSE_TRADING), remove countdown objects and exit
   if(tradeMode == NO_TRADE || tradeMode == PAUSE_TRADING) {
      class=class="str">"cmt">//--- Check if a countdown object exists on the chart
      if(ObjectFind(class="num">0, "NewsCountdown") >= class="num">0) {
         class=class="str">"cmt">//--- Delete the countdown object from the chart
         ObjectDelete(class="num">0, "NewsCountdown");
         class=class="str">"cmt">//--- Log that the trading is disabled and the countdown has been removed
         Print("Trading disabled. Countdown removed.");
      }
      class=class="str">"cmt">//--- Exit the function since trading is not allowed
      class="kw">return;
   }
   class=class="str">"cmt">//--- Begin pre-trade candidate selection section

   class=class="str">"cmt">//--- Define the lower bound of the event time range based on the user-defined start time offset
   class="type">class="kw">datetime lowerBound = currentTime - PeriodSeconds(start_time);
   class=class="str">"cmt">//--- Define the upper bound of the event time range based on the user-defined end time offset
   class="type">class="kw">datetime upperBound = currentTime + PeriodSeconds(end_time);
   class=class="str">"cmt">//--- Log the overall event time range for debugging purposes
   Print("Event time range: ", TimeToString(lowerBound, TIME_SECONDS), " to ", TimeToString(upperBound, TIME_SECONDS));

   class=class="str">"cmt">//--- Retrieve historical calendar values(news events) within the defined time range
   MqlCalendarValue values[];
   class="type">int totalValues = CalendarValueHistory(values, lowerBound, upperBound, NULL, NULL);
   class=class="str">"cmt">//--- Log the total number of events found in the specified time range
   Print("Total events found: ", totalValues);
   class=class="str">"cmt">//--- If no events are found, class="kw">delete any existing countdown and exit the function
   if(totalValues <= class="num">0) {
      if(ObjectFind(class="num">0, "NewsCountdown") >= class="num">0)
         ObjectDelete(class="num">0, "NewsCountdown");
      class="kw">return;
   }
}
class=class="str">"cmt">//--- Initialize candidate event variables for trade selection
class="type">class="kw">datetime candidateEventTime = class="num">0;
class="type">class="kw">string candidateEventName = "";
class="type">class="kw">string candidateTradeSide = "";
class="type">int candidateEventID = -class="num">1;
class=class="str">"cmt">//--- Loop through all retrieved events to evaluate each candidate for trading

for(class="type">int i = class="num">0; i < totalValues; i++) {
  class=class="str">"cmt">//--- Declare an event structure to hold event details
  MqlCalendarEvent event;
  class=class="str">"cmt">//--- Attempt to populate the event structure by its ID; if it fails, skip to the next event
  if(!CalendarEventById(values[i].event_id, event))
    class="kw">continue;

  class=class="str">"cmt">//----- Apply Filters -----

  class=class="str">"cmt">//--- If currency filtering is enabled, check if the event&class="macro">#x27;s currency matches the selected filters
  if(enableCurrencyFilter) {
    class=class="str">"cmt">//--- Declare a country structure to hold country details
    MqlCalendarCountry country;
    class=class="str">"cmt">//--- Populate the country structure based on the event&class="macro">#x27;s country ID
    CalendarCountryById(event.country_id, country);
    class=class="str">"cmt">//--- Initialize a flag to determine if there is a matching currency
    class="type">bool currencyMatch = false;
    class=class="str">"cmt">//--- Loop through each selected currency filter
    for(class="type">int k = class="num">0; k < ArraySize(curr_filter_selected); k++) {
      class=class="str">"cmt">//--- Check if the event&class="macro">#x27;s country currency matches the current filter selection
      if(country.currency == curr_filter_selected[k]) {
        class=class="str">"cmt">//--- Set flag to true if a match is found and break out of the loop
        currencyMatch = true;
        break;
      }
    }
    class=class="str">"cmt">//--- If no matching currency is found, log the skip and class="kw">continue to the next event
    if(!currencyMatch) {
      Print("Event ", event.name, " skipped due to currency filter.");
      class="kw">continue;
    }
  }

  class=class="str">"cmt">//--- If importance filtering is enabled, check if the event&class="macro">#x27;s impact matches the selected filters
  if(enableImportanceFilter) {
    class=class="str">"cmt">//--- Initialize a flag to determine if the event&class="macro">#x27;s impact matches any filter selection
    class="type">bool impactMatch = false;
    class=class="str">"cmt">//--- Loop through each selected impact filter option
    for(class="type">int k = class="num">0; k < ArraySize(imp_filter_selected); k++) {
      class=class="str">"cmt">//--- Check if the event&class="macro">#x27;s importance matches the current filter selection
      if(event.importance == imp_filter_selected[k]) {
        class=class="str">"cmt">//--- Set flag to true if a match is found and break out of the loop
        impactMatch = true;
        break;
      }
    }
    class=class="str">"cmt">//--- If no matching impact is found, log the skip and class="kw">continue to the next event
    if(!impactMatch) {
      Print("Event ", event.name, " skipped due to impact filter.");
      class="kw">continue;
    }
  }

  class=class="str">"cmt">//--- If time filtering is enabled and the event time exceeds the upper bound, skip the event
  if(enableTimeFilter && values[i].time > upperBound) {
    Print("Event ", event.name, " skipped due to time filter.");
    class="kw">continue;
  }