Articles with MQL5 programming examples

We want to create such an environment, which would provide access to data of indicators attached to a chart, and would have the following properties: absence of data copying; minimal modification of the code of available methods, if we need to use them; MQL code is preferable (of course, we have to use DLL, but we will use just a dozen of strings of C++ code). The article describes an easy method to develop a program environment for the MetaTrader terminal, that would provide means for accessing indicator buffers from other MQL programs.

The article gives an example of integrating MetaTrader 4 Client Terminal with MS SQL Server using a dll. Attached are both source codes in С++ and in MQL4, and a ready-made and compiled Visual C++ 6.0 SP5 project.

The idea of digital signal filtering has been widely discussed on forum topics about building trading systems. And it would be imprudent not to create a standard code of digital filters in MQL5. In this article the author describes the transformation of simple SMA indicator's code from his article "Custom Indicators in MQL5 for Newbies" into code of more complicated and universal digital filter. This article is a logical sequel to the previous article. It also tells how to replace text in code and how to correct programming errors.

Many researchers do not pay enough attention to determining the price behavior. At the same time, complex methods are used, which very often are simply “black boxes”, such as machine learning or neural networks. The most important question arising in that case is what data to submit for training a particular model.

In the article, we continue the development of the trading class by implementing the control over incorrect trading order parameter values and voicing trading events.

All channel indicators are displayed as three lines, including central, top and bottom lines. The drawing principle of the central line is similar to a moving average, while the moving average indicator is mostly used for drawing channels. The top and bottom lines are located at equal distances from the central line. This distance can be determined in points, as percent of price (the Envelopes indicator), using a standard deviation value (Bollinger Bands), or an ATR value (Keltner channel).

The article describes custom methods for assessing the trading history. Two classes have been written for downloading and analyzing history. The first of them collects the trading history and represents it as a summary table. The second one deals with statistics: it calculates a number of variables and builds charts for a more efficient evaluation of trading results.

In the first part of the article, I have described a modified ZigZag indicator and a class for receiving data of that type of indicators. Here, I will show how to develop indicators based on these tools and write an EA for tests that features making deals according to signals formed by ZigZag indicator. As an addition, the article will introduce a new version of the EasyAndFast library for developing graphical user interfaces.

The main difference of the trading system proposed in the article is the use of mathematical tools for analyzing stock quotes. The system applies digital filtering and spectral estimation of discrete time series. The theoretical aspects of the strategy are described and a test Expert Advisor is created.

The article considers the development of a simple multi-period indicator based on the DoEasy library. Let's improve the timeseries classes to receive data from any timeframes to display it on the current chart period.

The article proposes Kagi chart indicator with various charting options and additional functions. Also, indicator charting principle and its MQL5 implementation features are considered. The most popular cases of its implementation in trading are displayed - Yin/Yang exchange strategy, pushing away from the trend line and consistently increasing "shoulders"/decreasing "waists".

This article provides further description of the CStrategy trading engine. By popular demand of users, we have added pending order support functions to the trading engine. Also, the latest version of the MetaTrader 5 now supports accounts with the hedging option. The same support has been added to CStrategy. The article provides a detailed description of algorithms for the use of pending orders, as well as of CStrategy operation principles on accounts with the hedging option enabled.

MetaEditor 5 has the debugging feature. But when you write your MQL5 programs, you often want to display not the individual values, but all messages that appear during testing and online work. When the log file contents have large size, it is obvious to automate quick and easy retrieval of required message. In this article we will consider ways of finding errors in MQL5 programs and methods of logging. Also we will simplify logging into files and will get to know a simple program LogMon for comfortable viewing of logs.

In the previous article, we started developing a form class for controls. In this article, we are going to continue doing that by filling this class with methods for moving a form over the chart area. We will then integrate this interface component into the core of the library. Also, we will ensure that the color of a form control changes when the mouse cursor is hovering over it.

Is it allowed to trade this symbol on Monday? Is there enough money to open position? How big is the loss if Stop Loss triggers? How to limit the number of pending orders? Was the trade operation executed at the current bar or at the previous one? If a trade robot cannot perform this kind of verifications, then any trade strategy can turn into a losing one. This article shows the examples of verifications that are useful in any Expert Advisor.

In the previous articles, we started creating a large cross-platform library simplifying the development of programs for MetaTrader 5 and MetaTrader 4 platforms. We already have collections of historical orders and deals, market orders and positions, as well as the class for convenient selection and sorting of orders. In this part, we will continue the development of the base object and teach the Engine Library to track trading events on the account.

The article describes a method of modifying the code of a trading signal module for the implementation of the functionality allowing you to set pending orders at any distance from the current price: it may be the Close or Open price of the previous bar or the value of the moving average. There are plenty of options. Important is that you can set any opening price for a pending order. This article will be useful to traders who trade with pending orders.

In the article, we will consider a sample multi-symbol multi-period indicator using the timeseries classes of the DoEasy library displaying the chart of a selected currency pair on a selected timeframe as candles in a subwindow. I am going to modify the library classes a bit and create a separate file for storing enumerations for program inputs and selecting a compilation language.

In this article, we will continue to modify the Expert Advisor we have been working on throughout the preceding articles of the MQL5 Cookbook series. This time, the Expert Advisor will be enhanced with indicators whose values will be used to check position opening conditions. To spice it up, we will create a drop-down list in the external parameters to be able to select one out of three trading indicators.

In the article, we continue to develop the MQL application for working with optimization results. This time, we will show how to form the table of the best results after optimizing the parameters by specifying another criterion via the graphical interface.

Let us consider the button control. We will discuss examples of several classes for creating a simple button, buttons with extended functionality (icon button and split button) and interconnected buttons (button groups and radio button). Added to that, we will introduce some additions to existing classes for controls to broaden their capability.

Surfing the Internet, it is easy to find many strategies, which will give you a number of various recommendations. Let’s take an insider’s approach and look into the process of strategy creation, based on the differences in timezones on different continents.

The article describes the algorithm for implementing the OpenCL candlestick patterns tester in the "1 minute OHLC" mode. We will also compare its speed with the built-in strategy tester launched in the fast and slow optimization modes.

In this article, we continue studying the principles of working with Internet using HTTP requests and exchange of information with server. It describes new functions of the CMqlNet class, methods of sending information from forms and sending of files using POST requests as well as authorization on websites under your login using Cookies.

MQL5 Market has many products for sale but some of their descriptions leave much to be desired. Many texts are obviously in need of improvement, as common traders are not able to comprehend them. This article will help you to put your product in a favorable light. Use our recommendations to write an eye-catching description that will easily show your customers what exactly you are selling.

The article deals with the simultaneous launch of Expert Advisor testing on four different trading instruments. The final comparison of four testing reports is provided in a table similar to how goods are represented in online stores. An additional bonus is that distribution charts will be automatically created for each symbol.

In this article, I will continue the development of the basic graphical element class of all library graphical objects powered by the CCanvas Standard Library class. I will create the methods for drawing graphical primitives and for displaying a text on a graphical element object.

After we send a trading order to the server, we need to check the error codes or the absence of errors. In this article, we will consider handling errors returned by the trade server and prepare for creating pending trading requests.

In this article, we will consider the class of displaying text messages. Currently, we have a sufficient number of different text messages. It is time to re-arrange the methods of their storage, display and translation of Russian or English messages to other languages. Besides, it would be good to introduce convenient ways of adding new languages to the library and quickly switching between them.

The article deals with conflict-free trading of several experts on one МТ 4 Client Terminal. It will be useful for those who have basic command of working with the terminal and programming in MQL 4.

Environment MQL4 is based on the conception of safe "sandbox": reading and saving files using the language are allowed in some predefined folders only. This protects the user of MetaTrader 4 from the potential danger of damaging important data on the HDD. However, it is sometimes necessary to leave that safe area. This article is devoted to the problem of how to do it easily and correctly.

After the upgrade of the MATLAB package in 2015, it is necessary to consider a modern way of creating DLL libraries. The article uses a sample predictive indicator to illustrate the peculiarities of linking MetaTrader 5 and MATLAB using modern 64-bit versions of the platforms, which are utilized nowadays. With the entire sequence of connecting MATLAB considered, MQL5 developers will be able to create applications with advanced computational capabilities much faster, avoiding «pitfalls».

Expert Advisor Visual Wizard for MetaTrader 5 provides a highly intuitive graphical environment with a comprehensive set of predefined trading blocks that let you design Expert Advisors in minutes. The click, drag and drop approach of Expert Advisor Visual Wizard allows you to create visual representations of forex trading strategies and signals as you would with pencil and paper. These trading diagrams are analyzed automatically by Molanis’ MQL5 code generator that transforms them into ready to use Expert Advisors. The interactive graphical environment simplifies the design process and eliminates the need to write MQL5 code.

In this article, we will consider an example of developing a user interface with button controls. To convey the idea of interactivity to the user, buttons will change their colors when the cursor hovers over them. With the cursor being over a button, the button color will be slightly darkened, getting significantly darker when the button is clicked. Furthermore, we will add tooltips to each button, thus creating an intuitive interface.

In this article, we will consider such issues as including sound files in the file of the Expert Advisor, and thus adding sound notifications to trade events. The fact that the files will be included means that the sound files will be located inside the Expert Advisor. So when giving the compiled version of the Expert Advisor (*.ex5) to another user, you will not have to also provide the sound files and explain where they need to be saved.

This article has been made to show you how to use neural networks, via FANN2MQL, using an easy example: teaching a simple pattern to the neuralnetwork, and testing it to see if it can recognize patterns it has never seen.

Are you going to write your own indicator? Perhaps you will find that what you need among indicators already embedded in the client terminal. So why to reinvent the wheel? A summary table of integrated indicators' characteristics; special features and methods of attaching indicators to a chart; building of levels; displaying of indicators on different timeframes.