Golang 基础学习

17 OO Approach vs GO Approach

面向对象

type

receiver

17例子

type

// deck.go

package main
// create a new type of 'deck'
// which is a slice of strings
type deck []string   // 有点像声明类
}
 

// main.go

package main
import "fmt"

func main(){
    cards := deck{"Ace of Diamonds", newCard()}
    cards = append(cards, "six of spades")
    
    for i, card := range cards{
        fmt.Println(i, card)
    }
}

func newCard() string{
    return "Five of Diamonds"
}

receiver 接收器

// deck.go
package main

// create a new type of 'deck'
// which is a slice of strings

type deck []string   // 有点像声明类

// any variable of type "deck" now gets access to the "print" method
// 接收器为我们创建的变量设置方法
func (d deck) print(){   // 定义一个接收器，表示任意deck类型可以使用print方法
    for i, card := range d {  // 此处d类似于python中的self 
        fmt.Println(i, card)
    }
}
// type像声明类，receiver像类实例的方法


// main.go

package main
import "fmt"

func main(){
    cards := deck{"Ace of Diamonds", newCard()}
    cards = append(cards, "six of spades")
    cards.print()  // 接收器使用处
}

func newCard() string{
    return "Five of Diamonds"
}

21 Slice Range Syntax

切片，左闭右开

[0:2] //即0，1

22 multiple return values

func deal(d deck, handSize int)(deck, deck){
    return d[:handSize], d[handSize:]
}

deal("aaaaa", 1)

23 type convert

package main

func main(){
    greeting := "Hi there!"
    fmt.Println([]byte(greeting))

}
> [76 88 99 ]

24 Deck to String

// deck.go
package main

import (
    "fmt"
    "strings"
)

func (d deck) toString() string {
    return strings.Join([]string(d), ",")
}

//main.go
import "fmt"

func main() {
    cards := newDeck()
    fmt.Println(cards.toString())
}