go map学习笔记

go map note

1.声明和赋值

	var myGreeting map[string]string      	//声明map,可以直接make()

	myGreeting = make(map[string]string)	//声明后必须make才能赋值！！

	var myGreeting = make(map[string]string)	//直接make()的方式

	myGreeting := make(map[string]string)	//更简短的创建方式

	myGreeting := map[string]string{		//声明同时赋值的方式
		"Tim":   "Good morning!",
		"Jenny": "Bonjour!",
	}
	
	myGreeting["Tim"] = "Good morning."

	myGreeting["Jenny"] = "Bonjour."

2.修改删除等操作

	myGreeting["Harleen"] = "Howdy"

	delete(myGreeting, "two")

	val, exists := myGreeting[2]	//返回值和是否存在的bool值

3.遍历方法

	for key, val := range myGreeting {
		fmt.Println(key, " - ", val)
	}