MQL4 and MQL5 Programming Articles

This article considers BookEvent - a Depth of Market event, and the principle of its processing. An MQL program, handling states of Depth of Market, serves as an example. It is written using the object-oriented approach. Results of handling are displayed on the screen as a panel and Depth of Market levels.

In this article, we will continue to study fractals and will pay special attention to summarizing all the material. To do this, I will try to bring all earlier developments into a compact form which would be convenient and understandable for practical application in trading.

Every price action trader manually uses trendlines to confirm trends and spot potential turning or continuation levels. In this series on developing a price action analysis toolkit, we introduce a tool focused on drawing slanted trendlines for easy market analysis. This tool simplifies the process for traders by clearly outlining key trends and levels essential for effective price action evaluation.

In this article, I will create the signal collection class of the MQL5.com Signals service with the functions for managing signals. Besides, I will improve the Depth of Market snapshot object class for displaying the total DOM buy and sell volumes.

This is the first article of the MQL5 Cookbook series. I will start with simple examples to allow those who are taking their first steps in programming to gradually become familiar with the new language. I remember my first efforts at designing and programming trading systems which I may say was quite difficult, given the fact that it was the first programming language in my life. However, it turned out to be easier than I thought and it only took me a few months before I could develop a fairly complex program.

Matrices and vectors have been introduced in MQL5 for efficient operations with mathematical solutions. The new types offer built-in methods for creating concise and understandable code that is close to mathematical notation. Arrays provide extensive capabilities, but there are many cases in which matrices are much more efficient.

Finding rules for a trade system and programming them in an Expert Advisor is a half of the job. Somehow, you need to correct the operation of the Expert Advisor as it accumulates the results of trading. This article describes one of approaches, which allows improving performance of an Expert Advisor through creation of a feedback that measures slope of the balance curve.

Since its introduction, MetaTrader 5 provides multicurrency testing options. This possibility is often used by traders. However the function is not universal. The article presents several programs for drawing graphical objects on charts based on HTML and CSV trading history reports. Multicurrency trading can be analyzed in parallel, in several sub-windows, as well as in one window using the dynamic switching command.

In this article, technical indicators are treated as digital filters. Operation principles and basic characteristics of digital filters are explained. Also, some practical ways of receiving the filter kernel in MetaTrader 5 terminal and integration with a ready-made spectrum analyzer proposed in the article "Building a Spectrum Analyzer" are considered. Pulse and spectrum characteristics of the typical digital filters are used as examples.

In this article, we’ve transitioned from manually coding candlestick‑pattern detection in Python to leveraging TA‑Lib, a library that recognizes over sixty distinct patterns. These formations offer valuable insights into potential market reversals and trend continuations. Follow along to learn more.

The article opens up a new large section of the library for working with graphics. In the current article, I will create the mouse status object, the base object of all graphical elements and the class of the form object of the library graphical elements.

The MetaTrader 5 platform allows developing and testing trading robots that simultaneously trade multiple financial instruments. The built-in Strategy Tester automatically downloads required tick history from the broker's server taking into account contract specifications, so the developer does not need to do anything manually. This makes it possible to easily and reliably reproduce trading environment conditions, including even millisecond intervals between the arrival of ticks on different symbols. In this article we will demonstrate the development and testing of a spread strategy on two Moscow Exchange futures.

In the first part, we started creating a large cross-platform library simplifying the development of programs for MetaTrader 5 and MetaTrader 4 platforms. Further on, we implemented the collection of history orders and deals. Our next step is creating a class for a convenient selection and sorting of orders, deals and positions in collection lists. We are going to implement the base library object called Engine and add collection of market orders and positions to the library.

Let's continue exploring various controls and this time turn our attention to scrollbar. Just like in the previous article entitled "MQL5 Cookbook: Indicator Subwindow Controls - Buttons", all operations will be performed in the indicator subwindow. Take a moment to read the above mentioned article as it provides a detailed description of working with events in the OnChartEvent() function, while this point will only be casually touched upon in this article. For illustrative purposes, this time around we will create a vertical scrollbar for a large list of all financial instrument properties that can be obtained using MQL5 resources.

We continue the development of a large cross-platform library simplifying the development of programs for MetaTrader 5 and MetaTrader 4 platforms. In the tenth part, we resumed our work on the library compatibility with MQL4 and defined the events of opening positions and activating pending orders. In this article, we will define the events of closing positions and get rid of the unused order properties.

The article describes a method of changing the external parameters of MQL4 programs on-the-fly, without restarting.

We continue to study machine learning methods. With this article, we begin another big topic, Reinforcement Learning. This approach allows the models to set up certain strategies for solving the problems. We can expect that this property of reinforcement learning will open up new horizons for building trading strategies.

Hard to interpret Ichimoku signals? This article introduces some principles of formalizing values and signals of Ichimoku Kinko Hyo. For visualization of its usage the author chose the currency pair EURUSD based on his own preferences. However, the indicator can be used on any currency pair.

Pivot point is a line in the price chart that shows the further trend of a currency pair. If the price is above this line, it tends to grow. If the price is below this line, accordingly, it tends to fall.

MQL5 Standard Library makes your life as a developer easier. Nevertheless, it does not implement all the needs of all developers in the world, so if you feel that you need some more custom stuff you can take a step further and extend. This article walks you through integrating MetaQuotes' Zig-Zag technical indicator into the Standard Library. We get inspired by MetaQuotes' design philosophy to achieve our goal.

Is it possible to predict the behavior of the market for a short upcoming interval of time, based on the recurring tendencies of candle directions, at specific times throughout the day? That is, If such an occurrence is found in the first place. This question has probably arisen in the mind of every trader. The purpose of this article is to attempt to predict the behavior of the market, based on the statistical recurrences of candle directions during specific intervals of time.

With this article we begin chapter nine of series of articles dedicated to creating graphical interfaces in MetaTrader trading terminals. It consists of two chapters where new elements of controls and interface, such as color picker, color button, progress bar and line chart are presented.

This article describes techniques of operating with Kohonen maps. The subject will be of interest to both market researchers with basic level of programing in MQL4 and MQL5 and experienced programmers that face difficulties with connecting Kohonen maps to their projects.

We continue to develop the Multiline Text box control. This time our task is to implement an automatic word wrapping in case a text box width overflow occurs, or a reverse word wrapping of the text to the previous line if the opportunity arises.

If an indicator uses values of many other indicators for its calculations, it consumes a lot of memory. The article describes several methods of decreasing the memory consumption when using auxiliary indicators. Saved memory allows increasing the number of simultaneously used currency pairs, indicators and strategies in the client terminal. It increases the reliability of trade portfolio. Such a simple care about technical resources of your computer can turn into money resources at your deposit.

In the previous chapter of the first part of the series about graphical interfaces, the form class was enriched by methods which allowed managing the form by pressing its controls. In this article, we will test our work in different types of MQL program such as indicators and scripts. As the library was designed to be cross-platform so it could be used in all MetaTrader platforms, we will also test it in MetaTrader 4.

Everyone starting to work in Forex tries to answer these questions. But not everyone finds the answer, even after many years of hard work and search. I personally have answered this question, as well as many other questions of this article. As a result of these answers a way of creating an efficient trading strategy was determined.

Hiding of the implementation details of classes/functions in an .ex5 file will enable you to share your know-how algorithms with other developers, set up common projects and promote them in the Web. And while the MetaQuotes team spares no effort to bring about the possibility of direct inheritance of ex5 library classes, we are going to implement it right now.

The main point of this article is to show a practical way to implement an effective MM. This can be achieved only by using a certain kind of strategies that we need to identify and describe first. In the following we’ll cover the basic concepts of how to build such a strategy and we’ll point out the common mistakes which always end up in draining a trader’s account.

Based on universal tools designed for working with Kohonen networks, we construct the system of analyzing and selecting the optimal EA parameters and consider forecasting time series. In Part I, we corrected and improved the publicly available neural network classes, having added necessary algorithms. Now, it is time to apply them to practice.