The difference between golang pointer methods

Golang is a language that supports object-oriented programming, and pointers and methods are often used in actual development. A pointer is a variable that stores the memory address of a variable. A method is a function that specifies a type. There is a difference between pointer methods and non-pointer methods in Golang. This article will explore the differences and uses of these two methods.

1. Pointer method

The pointer method is a method bound to a structure pointer. Pointer methods have the following characteristics:

1. The receiver type of a pointer method is a pointer to a certain type.
2. Pointer methods can modify the value pointed to by the receiver.
3. If a type's method needs to modify its receiver itself, it must use pointer methods.

For example, we define a structure type:

type Rectangle struct {
    width  float64
    height float64
}

We can use pointer methods to modify instances of this structure:

func (r *Rectangle) SetProperty(width, height float64) {
    r.width = width
    r.height = height
}

In the above method, Receiver (r *Rectangle) is a pointer to a Rectangle structure. This method is used to set the properties of Rectangle.

2. Non-pointer method

The non-pointer method is a method bound to a structure. It accepts a copy of the structure as the receiver parameter. The non-pointer method has the following characteristics :

1. The receiver type of a non-pointer method is a copy of the value of the type.
2. Non-pointer methods cannot modify the value of the receiver.

For example, we define a structure type:

type Rectangle struct {
    width  float64
    height float64
}

We can use non-pointer methods to calculate the area of ​​the structure:

func (r Rectangle) GetArea() float64 {
    return r.width * r.height
}

In the above method , the receiver r Rectangle is a copy of the value of the Rectangle structure. This method returns the area of ​​the rectangle.

3. The difference between pointer methods and non-pointer methods

1. Pointer methods can modify the properties in the receiver, but non-pointer methods cannot.
2. Pointer methods can avoid copying the object when called because they can directly access the address of the object. This feature is particularly useful when working with large structures.
3. Non-pointer methods must copy the entire object when called, which may cause performance issues.
4. When defining a method, you can use non-pointer methods if you do not need to modify the receiver itself, otherwise you must use pointer methods.

For example, we can use pointer methods to modify the structure:

func main() {
    rect := Rectangle{width: 10, height: 5}
    fmt.Println("Width:", rect.width, "Height:", rect.height)
    rect.SetProperty(20, 10)
    fmt.Println("Width:", rect.width, "Height:", rect.height)
}

Output result:

Width: 10 Height: 5
Width: 20 Height: 10

4. Summary

In Golang Among them, pointer methods and non-pointer methods have their own advantages, disadvantages and usage scenarios. When defining methods, you need to consider the usage of the object and business needs, and choose an appropriate method to write code. Proper use of both methods can improve code readability and performance.

The above is the detailed content of The difference between golang pointer methods. For more information, please follow other related articles on the PHP Chinese website!