语法与结构

Lesson Overview

In "MQL5 EA Programming Intro" → "MQL5 基础", this lesson "语法与结构" builds knowledge you can apply immediately.

MQL5程序按事件组织：OnInit初始化、OnTick处理报价、OnDeinit释放资源。变量类型、作用域与返回状态影响运行；不能将MT4代码不经修改当MT5。 阅读配套mq5→标输入/全局/局部变量→列事件入口→核初始化失败路径→在MetaEditor记录编译版本。 本课作业：指出指标句柄为什么不能在每个tick无条件重建，以及退出时应做什么。

Core Concepts

These points align with the video walkthrough—take notes as you watch.

• ▸MQL5程序按事件组织：OnInit初始化、OnTick处理报价、OnDeinit释放资源。变量类型、作用域与返回状态影响运行；不能将MT4代码不经修改当MT5。
• ▸阅读配套mq5→标输入/全局/局部变量→列事件入口→核初始化失败路径→在MetaEditor记录编译版本。
• ▸本课作业：指出指标句柄为什么不能在每个tick无条件重建，以及退出时应做什么。

Practical Application

After studying, complete the companion practice lesson to move from understanding to doing.

• ▸Follow along in Jupyter or VS Code
• ▸Log how parameter changes affect backtest results
• ▸Submit a reproducible analysis notebook

FAQ

• ▸Q: How does this lesson fit the course? A: Part of "MQL5 基础"—follow the curriculum order.
• ▸Q: What do I need? A: Demo account and notes; quant lessons need a Python environment.
• ▸Q: How do I know I've mastered it? A: Pass the quiz and explain three key points of 语法与结构 on your own.