The difference between * and & in Go language

The difference between * and & in Go language

---

1. to sum up
2. Example

I'm always confused about the difference between * and &, so today I deliberately summarized it.

---

1. Summary

1. & Is the address character.
2. * It can indicate that a variable is a pointer type, or it can indicate the storage unit pointed to by the pointer type variable, that is, the value pointed to by this address.

---

2. Example

1. Code

type Person struct {
    
    
	name string
	age int
}

func main() {
    
    
	// & 是取地址符，取到Person类型对象的地址
	// 声明一个Person类型的结构体
	Bob := Person{
    
    "Bob", 20}
	fmt.Println("Bob:", Bob, " &Bob:", &Bob)

	// 声明一个Person类型的指针
	Lisa := &Person{
    
    "Lisa",30}
	fmt.Println("Lisa:",Lisa,"&Lisa:",&Lisa)

	// * 可以表达一个变量是指针类型
	var John *Person = &Person{
    
    
		name: "John",
		age:  40,
	}
	fmt.Println("John:",John," &John:",&John)

	// * 也可以表示指针类型变量所指向的存储单元，也就是这个地址所指向的值
	fmt.Println("*John:",*John)

	//函数参数是指针的话，会修改原来的数据
	changName(John)
	fmt.Println("*John:",*John)
}

func changName(p *Person) {
    
    
	// p 是一个指针
	//如果是基本数据类型 [p.name = "China"] == [(*p).name = "China"]
	//其他类型则必须用 * 取值
	(*p).name = "China"
	p.age = 100
}

2. Output result