Program Properties (#property)

Every MQL4-program allows to specify additional specific parameters named #property that help client terminal in proper servicing for programs without the necessity to launch them explicitly. This concerns external settings of indicators, first of all. Properties described in included files are completely ignored. Properties must be specified in the main mq4 file.

#property identifier value

The compiler will write declared values in the configuration of the module executed.

Constant	Type	Description
strict		Compiler directive for strict compilation mode (see Updated MQL4)
icon	string	Path to the file of an image that will be used as an icon of the EX4 program. Path specification rules are the same as for resources. The property must be specified in the main module with the MQL4 source code. The icon file must be in the ICO format.
link	string	Link to the company website
copyright	string	The company name
version	string	Program version, maximum 31 characters
description	string	Brief text description of a MQL4-program. Several description can be present, each of them describes one line of the text. The total length of all description can not exceed 511 characters including line feed.
stacksize	int	MQL4 program stack size. The stack of sufficient size is necessary when executing function recursive calls. When launching a script or an Expert Advisor on the chart, the stack of at least 8 MB is allocated. In case of indicators, the stack size is always fixed and equal to 1 MB. When a program is launched in the strategy tester, the stack of 8 MB is always allocated for it.
library		A library; no start function is assigned, functions with the export modifier can be imported in other MQL4-programs
indicator_chart_window		Show the indicator in the chart window
indicator_separate_window		Show the indicator in a separate window
indicator_height	int	Fixed height of the indicator subwindow in pixels (property INDICATOR_HEIGHT)
indicator_buffers	int	Number of buffers for indicator calculation
indicator_minimum	double	The bottom scaling limit for a separate indicator window
indicator_maximum	double	The top scaling limit for a separate indicator window
indicator_labelN	string	Sets a label for the N-th graphic series displayed in DataWindow
indicator_colorN	color	The color for displaying line N, where N is the number of graphic series; numbering starts from 1
indicator_widthN	int	Line thickness in graphic series, where N is the number of graphic series; numbering starts from 1
indicator_styleN	int	Line style in graphic series, specified by the values of ENUM_LINE_STYLE. N is the number of graphic series; numbering starts from 1
indicator_typeN	int	Type of indicator drawing style. N is the number of graphic series; numbering starts from 1
indicator_levelN	double	Horizontal level of N in a separate indicator window
indicator_levelcolor	color	Color of horizontal levels of the indicator
indicator_levelwidth	int	Thickness of horizontal levels of the indicator
indicator_levelstyle	int	Style of horizontal levels of the indicator
script_show_confirm		Display a confirmation window before running the script
script_show_inputs		Display a window with the properties before running the script and disable this confirmation window
tester_file	string	File name from <terminal_data_folder>\MQL4\Files\ to be sent to a virtual server
tester_indicator	string	Indicator file name from <terminal_data_folder>\MQL4\Indicators\ to be sent to a virtual server
tester_library	string	Library file name from <terminal_data_folder>\MQL4\Libraries\ to be sent to a virtual server

tester_file, tester_indicator and tester_library properties are necessary for describing the list of the files required for working in virtual hosting.

Indicator files called in iCustom() function with a fixed name, as well as all library files used in MQL4 programs are copied automatically during the migration.

Find out more about migration of programs in the article "How to Prepare a Trading Account for Migration to Virtual Hosting".

Sample code for moving files to a hosting

#property tester_file "trade_patterns.csv" // file with the data to be read by an Expert Advisor
#property tester_indicator "smoothed_ma.ex4" // file with a custom indicator specified in iCustom() as a variable

Example of an implicit indication of an indicator name in the code

string indicator_name="smoothed_ma.ex4";
double val=iCustom(NULL,0,indicator_name,13,1,0);

Sample Task of Description and Version Number

#property version "3.70" // Current version of the Expert Advisor
#property description "ZigZag universal with Pesavento Patterns"
#property description "At the moment in the indicator several ZigZags with different algorithms are included"
#property description "It is possible to embed a large number of other indicators showing the highs and"
#property description "lows and automatically build from these highs and lows various graphical tools"

Example of displaying description and version at program startup

Macro substitution (#define)Including Files (#include)