【Golang】map的使用

map声明的方式

    //声明
	var m map[string]string
	//在使用map之前，先make，make的作用就是给map分配空间
	m = make(map[string]string)
	m["lover"] = "Yzx"
	m["friend1"] = "Zxw"
	m["friend2"] = "Zzc"
	fmt.Println(m) //map[friend1:Zxw friend2:Zzc lover:Yzx]

	//第二种声明方式
	m2 := make(map[string]string, 10)
	m2["Math"] = "100"
	m2["English"] = "200"
	m2["Chinese"] = "150"
	fmt.Println(m2) //map[Chinese:150 English:200 Math:100]

	//第三种声明方式
	m3 := map[string]int{
		"Math":    50,
		"Chinese": 80,
		"English": 90,
	}

结果如下： 

map的使用

scoreMap := make(map[string]int)
	scoreMap["Math"] = 100
	scoreMap["English"] = 200
	scoreMap["Chinese"] = 150
	//遍历
	for key, value := range scoreMap {
		fmt.Println("key:", key, "value:", value)
	}
	
	//删除
	delete(scoreMap, "Math")
	
	//修改
	scoreMap["English"] = 100
	fmt.Println("-------------")
	
	//遍历
	for key, value := range scoreMap {
		fmt.Println("key:", key, "value:", value)
	}