Hey there! Let's tackle this news filter problem for your MQL4 EA. Ditching the ffcal indicator and going for a more direct approach makes total sense if you want full control over how each news event is handled. Here are a few proven strategies I’ve used with success:

1. Pull News Data via a Financial API (Most Flexible) #

This is the most robust method—you get structured, real-time news data that your EA can parse and act on individually. Here’s how to implement it:

Step-by-Step Breakdown #

• Pick a financial news API: Look for one that returns data in JSON or XML format (easier to parse). Many offer free tiers for non-commercial use, with fields like event time, currency pair, importance level, and event description.
• Use MQL4’s WebRequest(): This function lets your EA send HTTP requests to the API. You’ll need to enable web access in your MT4 terminal settings (Tools > Options > Expert Advisors > Allow WebRequest for listed URLs).
• Parse the API response: MQL4 doesn’t have built-in JSON parsing, so you can either write a simple custom parser for your target API’s format, or use a community-developed parsing library (like JSONParser.mqh—just search the MQL4 community for open-source options).
• Store and process events: Save parsed news events into a structured array, then check against the current time and active currency pairs to trigger custom logic.

Code Snippets to Get Started #

First, define a struct to hold news event details:

struct NewsEvent {
   datetime eventTime;      // UTC timestamp of the news
   string currencyPair;     // Associated pair (e.g., "EUR", "USD" for EURUSD-relevant news)
   int importance;          // 1=Low, 2=Medium, 3=High
   string eventDesc;        // Human-readable event name
};

NewsEvent newsEvents[]; // Array to store fetched news

Example function to fetch and parse news:

bool FetchLatestNews() {
   // Replace with your API endpoint and parameters (e.g., filter by currency, importance)
   const string API_URL = "YOUR_API_ENDPOINT?params=...";
   char response[];
   int httpStatusCode;

   // Send GET request to the API
   if(!WebRequest("GET", API_URL, NULL, NULL, 5000, NULL, 0, response, httpStatusCode)) {
      Print("Failed to fetch news. Error: ", GetLastError(), " | HTTP Code: ", httpStatusCode);
      return false;
   }

   // Convert response to string and parse into newsEvents array
   string responseStr = CharArrayToString(response);
   ParseNewsResponse(responseStr, newsEvents); // Implement this parser based on your API's format
   return true;
}

Core filter logic to handle each event individually:

void ExecuteNewsFilter() {
   datetime now = TimeCurrent();
   const int PRE_NEWS_WINDOW = 15 * 60; // 15 minutes before news
   const int POST_NEWS_WINDOW = 30 * 60; // 30 minutes after news

   for(int i = 0; i < ArraySize(newsEvents); i++) {
      datetime eventStart = newsEvents[i].eventTime - PRE_NEWS_WINDOW;
      datetime eventEnd = newsEvents[i].eventTime + POST_NEWS_WINDOW;

      // Check if current time is in the news window and the event affects the active symbol
      if(now >= eventStart && now <= eventEnd && StringFind(Symbol(), newsEvents[i].currencyPair) != -1) {
         switch(newsEvents[i].importance) {
            case 3: // High-impact news
               CloseAllActiveOrders(); // Custom function to close all positions
               global_allowTrading = false; // Global flag to block new orders
               break;
            case 2: // Medium-impact
               AdjustPositionSLTP(); // Widen stop-loss/take-profit to avoid volatility spikes
               break;
            case 1: // Low-impact
               // Optional: Reduce position size or do nothing
               break;
         }
      }
   }
}

2. Preload Local News Data (Offline-Friendly) #

If you don’t want to rely on external APIs, you can preload news events into a local file (like CSV) and read it during EA initialization:

• Create a CSV file with columns: EventTime(UTC), Currency, Importance, Description
• Read the file in MQL4 using FileOpen(), FileReadString(), and parse each line into your NewsEvent array
• Update the file regularly to keep news data current

This works well for testing or if your EA needs to run without internet access, but you lose real-time updates.

Key Considerations #

• Timezone consistency: Always use UTC timestamps (MT4’s TimeCurrent() is UTC) to avoid mismatches with API data
• Rate limiting: Don’t spam API requests—add a cooldown period (e.g., fetch news every 15 minutes)
• Broker restrictions: Some brokers block WebRequest()—check your broker’s terms or test in a demo account first

内容的提问来源于stack exchange，提问作者Skillz