table of Contents
table of Contents
@
Statements and methods of use
receiver
- Go in, although not class, but still there is method
- Is achieved by the receiver display shows a type of a combination
type A struct {
Name string
}
type B struct {
Name string
}
func main(){
a := A{}
a.Print()
b := B{}
b.Print()
}
func (a A) Print(){
fmt.Println("A")
}
func (b B) Print(){
fmt.Println("B")
}
//就像重载一样，但是不是(a A)(b B)就是receiver
/*
> Output:
command-line-arguments
A
B
*/Method overloading does not exist
- Absence of method overloading, following a case like this does not exist
func (a A) Print(){
fmt.Println("A")
}
func (a A) Print(b int){
fmt.Println("A")
}- Only the type defined in the same way as a package
- receiver can be a value or a pointer type
type A struct {
Name string
}
type B struct {
Name string
}
func main(){
a := A{}
a.Print()
fmt.Println(a.Name)
b := B{}
b.Print()
fmt.Println(b.Name)
}
//指针传递
func (a *A) Print(){
a.Name="AA"
fmt.Println("A")
}
//值传递
func (b B) Print(){
b.Name="BB"
fmt.Println("B")
}
/*
> Output:
command-line-arguments
A
AA
B
<空格>
> Elapsed: 6.294s
*/- Can use the value or pointer to call the method,
a.Print()the compiler will automatically transitioned
Type aliases and methods
- go language requires mandatory conversion, but also because of this
- Alias does not have the type of method of the underlying type of incidental
type TZ int
func main(){
var a TZ
a.Print()
}
func (a *TZ) Print(){
fmt.Println("TZ")
}
/*
> Output:
command-line-arguments
TZ
*/Method Value与Method Expression
- In a sense, the function is syntactic sugar, because the receiver is actually received by the first method parameter (Method Value vs. Method Expression)
//method value
a.Print()
//method expression
(*TZ).Print(&a)Both the output of the same
- If the outer structure and the embedded structure is present method with the same name, the priority call an external configuration of a method of
Method name conflicts with field access
- Method can be called the structure of the non-public field (private), the function can be accessed in main (), is the current authority of this package are visible
type A struct{
name string
}
func main(){
a := A{}
a.Print()
fmt.Println(a.name)
}
func (a *A) Print(){
a.name="123"
fmt.Println(a.name)
}
/*
> Output:
command-line-arguments
123
123
*/example
type A int
func (a *A) Increase(){
*a += 100
}
func (a *A)Increase2(num A) {
*a += num
}
func main(){
//显示类型声明，不要用a := 0,这样就是int了
var a A
a=0
a.Increase()
fmt.Println(a)
a.Increase2(100)
fmt.Println(a)
}
/*
> Output:
command-line-arguments
100
200
*/tips
The difference between the methods and functions
Methods: func (a A) add(num int) int {}
Functions:func add(num1 int,num2 int) int {}
The difference between methods and functions, methods, after the func keyword is a recipient rather than a function name, the recipient may be a type of their own definition, this type can be a struct, interface, and even we can redefine the basic data types.