Expert Advisor Programming

Introduction 1

About This Book 2

A Note About MQL 5 2

Conventions Used In This Book 3

An Introduction to MQL 4

Introduction to MetaEditor 4

Basic Concepts 7

Layout of an MQ4 File 14

Order Placement 20

Bid, Ask & Spread 20

Order Types 20

The Order Placement Process 21

OrderSend() 22

Calculating Stop Loss & Take Profit 25

Retrieving Order Information 32

Closing Orders 34

A Simple Expert Advisor 36

Advanced Order Placement 42

Order Modification 42

Verifying Stops and Pending Order Prices 45

Calculating Lot Size 49

Other Considerations 52

Putting It All Together 57

Working with Functions 64

Add Stop Loss and Take Profit 73

Using Include Files 74

Using Libraries 74

A Simple Expert Advisor (with Functions) 75

Order Management 80

The Order Loop 80

Order Counting 82

Trailing Stops 87

Updating the Expert Advisor 92

Order Conditions and Indicators 94

Price Data 94

Indicators 95

Indicator Constants 102

Evaluating Trade Conditions 103

Comparing Indicator Values Across Bars 108

Working with Time and Date 112

Datetime Variables 112

Date and Time Functions 114

Creating A Simple Timer 115

Execute On Bar Open 117

Tips and Tricks 122

Escape Characters 122

Using Chart Comments 122

Check Settings 123

Demo or Account Limitations 124

MessageBox() 125

Email Alerts 127

Retry on Error 128

Using Order Comments As an Identifier 131

Margin Check 132

Spread Check 132

Multiple Orders 133

Global Variables 136

Check Order Profit 137

Martingale 138

Debugging Your Expert Advisor 141