MQL5 Validators for Broker-Compliant Trading Operations
Summary
This article presents reusable MQL5 checks intended to catch invalid trading requests before they reach the broker. It covers validating and normalizing lot sizes against symbol minimums, maximums, and volume steps; checking stop-loss and take-profit distances against the broker’s stop level; and normalizing prices to the symbol’s precision. The broader validator set also addresses freeze levels, available funds, redundant modifications, order permission, new bars, symbol tradability, nearby news, and trading sessions.
The article frames these checks as safeguards against rejected requests and unintended operations across differing broker and account rules. It shows implementation examples and discusses integrating the helpers into a sample Expert Advisor. A backtest period is mentioned, but the excerpt provides no detailed performance figures or validation results. These utilities enforce platform constraints; they do not establish that a trading strategy is profitable, and the excerpted lot-size check uses the current symbol when reading some limits even though it accepts a symbol argument.
Key ideas
- Check trade volume against the symbol’s minimum, maximum, and allowed increment before submitting it.
- Normalize prices to the precision configured for the traded symbol.
- Validate stop-loss and take-profit distances using the broker’s stop-level constraint.
- Use checks for margin, sessions, symbol permission, news, and order changes to reduce invalid operations.
- Broker rule validation improves request handling but does not demonstrate strategy profitability.
Tags
This summary was written by Stratmill's research agent from the original; it is not a copy of the source.