MT4/MQL4 entry to proficient foreign exchange EA tutorial Lesson 1 Getting to know MetaEditor

​1. Open MetaEditor.Open the MT4 trading platform and click on the following figure in the navigation bar, or open it with the shortcut key on the desktop.

2. Get to know MetaEditor

Main file structure

①EA program folder, which stores mq4 files and compiled executable files ex4.

②A folder for storing arbitrary files, such as audio files, etc.

③The folder where pictures are stored.

④Function library folder, store mqh file.
⑤The indicator signal folder, which stores the mq4 file and the compiled executable file ex4.
⑥Database folder, store external program files, DLL files, etc.

⑦Script folder, store script files.

Start EA Journey - "Hello World"

1. Click Expert, right-click -> New File

Select the EA template, click Next

Fill in the EA name HelloWorld and click Next

Uncheck the option, click Next

Uncheck the option and click Next

Click Done

Recognize the code structure

Start writing code

Add printf() function inside each function.

int OnInit()

{

//—

printf("Initialization: Hello World!!!");

//—

return(INIT_SUCCEEDED);

}

void OnDeinit(const int reason)

{

//—

printf("Deinitialization: Hello World!!!");

}

void OnTick()

{

//—

printf("Hello World!!!");

}

Click the green button in the navigation bar to compile

Click OK

MT4 platform terminal EA option to see the print result: one initialization: Hello World!!! and a series of Hello World!!!

Go back to MetaEditor, click the red button to stop debugging

Stop the test with a deinitialization: HelloWorld!!!

Function and function explanation
OnInit(): Initialization function function, which is only executed once when the EA program is loaded and running, and will not be executed after that, and returns integer data.
OnDeinit(): Deinitialization function, executed once when the EA program is unloaded, and returns an empty type.
OnTick(): EA main function program, executed once when each tick is generated, and returns an empty type.

The execution result of the above HelloWorld EA,
The EA program loads the printf() function in the OnInit() function and executes it once, so "Initialization: HelloWorld!!!" appears once.
The OnTick() function is executed multiple times because of the intensive exchange rate quotes, so there are multiple "HelloWorld!!!"
When the EA program stops debugging, OnDeinit() is executed once, so "Deinitialization: HelloWorld!!!" is printed once

If you want to do good work, you must first sharpen your tools. The most important thing in trading is to abide by the rules and strictly implement them.Pay attention to the official account, learn MQL entry to master EA tutorials, write your own EA freely, and forge your own magic weapon.