Go语言基础

代码虽然简单，但是还是需要自己手动去写一遍才知道其中的道理。

package mainimport ("container/list"_ "container/list""flag"_ "flag""fmt""time"
)//使用flag从命令行中读取参数，不知道用来干嘛
func pack_flag_test(){surname := flag.String("surname","luo","您的姓")var personalName stringflag.StringVar(&personalName,"personalName","xiaoer","您的名")id := flag.Int("id",0,"您的ID")//解析命令行参数flag.Parse()fmt.Printf("I am %v%v, and my id is %v\n",*surname,personalName,*id)
}//指针操作
func pack_point_operate(){str := "Golang is good"strPrt := &str //取地址fmt.Printf("str type is %T,value is %v,address is %p\n", str, str, &strPrt)fmt.Printf("strPrt type is %T,value is %v\n", strPrt, strPrt)newStr := *strPrt  //解引用，拷贝内容，但是地址不是原来str的地址fmt.Printf("newStr type is %T,value is %v,address is %p\n", newStr, newStr, &newStr)
}//变量命名别名
type aliasInt = int
//定义新的类型
type myInt int
func pack_alias_test(){var alias aliasIntfmt.Printf("alias value is %v, type is %T\n", alias, alias)var val myIntfmt.Printf("val value is %v, type is %T\n", val, val)/** 结果：* alias value is 0, type is int* val value is 0, type is main.myInt*/
}//if与switch
func if_switch_test(name string, age int){if age >= 0 {age += 1}else if age < 0 {age = 1}/* switch语句1，不需要使用 break2，穿透关键字 fallthrough3，可以使用字符串和数值等*/switch name {case "xiaoming":fmt.Printf("I am xiaoming\n")//不需要使用breakcase "DD":fmt.Printf("I am DD\n")//不需要使用breakcase "":fmt.Printf("NULL\n")fmt.Printf("from fallthrough\n")fallthroughdefault:fmt.Printf("to fallthrough\n")}var i intfor i=0;i<=10;i++{fmt.Printf("i:%d\n",i)}
}//常用的容器
/*
1，数组
2，切片
3，列表
4，字典*/
func container_test(){//数组初始化的方法1var array [10] stringarray[0] = "这是第一个字符串"array[1] = "second"fmt.Printf("array:%v\n",array)//数组初始化的方法2array2 :=[...]string{"one","two","three"}fmt.Printf("array2:%v\n",array2)//数组初始化的方法3,指针操作数组array3 := new([3]string)array3[0] = "这是第一个字符串array3"array3[1] = "array3 second"//Println打印输出指针fmt.Println(*array3)//切片source := [...]int{1,2,3}sli := source[0:1]fmt.Printf("sli value is %v\n",sli)fmt.Printf("sli len is %v\n", len(sli))fmt.Printf("sli cap is %v\n",cap(sli))/*结果sli value is [1]sli len is 1sli cap is 3*///动态创建切片sli2 := make([]int, 2, 4)fmt.Printf("sli2 value is %v\n",sli2)fmt.Printf("sli2 len is %v\n", len(sli2))fmt.Printf("sli2 cap is %v\n",cap(sli2))/*sli2 value is [0 0]sli2 len is 2sli2 cap is 4*///声明切片sli3 := []int {1,2,3,4,5,6,7}sli3_c1 := sli3[0:2]//如果从0开始切的话，容量将保留原来的大小，即尾部不变，开始可变sli3_c2 := sli3[1:2]fmt.Printf("sli3 value is %v\n",sli3)fmt.Printf("sli3 len is %v\n", len(sli3))fmt.Printf("sli3 cap is %v\n",cap(sli3))fmt.Printf("sli3_c1 value is %v\n",sli3_c1)fmt.Printf("sli3_c1 len is %v\n", len(sli3_c1))fmt.Printf("sli3_c1 cap is %v\n",cap(sli3_c1))fmt.Printf("sli3_c2 value is %v\n",sli3_c2)fmt.Printf("sli3_c2 len is %v\n", len(sli3_c2))fmt.Printf("sli3_c2 cap is %v\n",cap(sli3_c2))/*sli value is [1]sli len is 1sli cap is 3sli2 value is [0 0]sli2 len is 2sli2 cap is 4sli3 value is [1 2 3 4 5 6 7]sli3 len is 7sli3 cap is 7sli3_c1 value is [1 2]sli3_c1 len is 2sli3_c1 cap is 7sli3_c2 value is [2]sli3_c2 len is 1sli3_c2 cap is 6*///切片添加元素new_append := append(sli3, 10)fmt.Printf("new_append value is %v\n",new_append)fmt.Printf("new_append len is %v\n", len(new_append))fmt.Printf("new_append cap is %v\n",cap(new_append))/*new_append value is [1 2 3 4 5 6 7 10]new_append len is 8new_append cap is 14     #翻倍了*///列表tmpList := list.New()for i:=1; i<10;i++{tmpList.PushBack(i)}first_List := tmpList.PushFront(0)tmpList.Remove(first_List)for i:=tmpList.Front(); i != nil;i=i.Next(){fmt.Print(i.Value,"\n")}//字典diction := make(map[int]string)diction[0] = "xx"diction[1] = "yy"diction[3] = "zz"diction2 := map[int]string{0:"aa",1:"bb",2:"cc",}fmt.Printf("id %v is %v\n",2,diction2[2])//遍历nums := [...]int{1,2,3,4,5,6,7,8,9}for k,v := range nums{fmt.Println(k,v,"")}tmpMap := map[int]string{0:"aa",1:"bb",2:"cc",}for k,v := range tmpMap{fmt.Println(k,v,"")}
}//命名返回值方法，需要写return，但是不可与非命名返回值混合使用
func div_func_test(dividend ,divisor int)(quotient, remainder int){quotient = dividend / divisorremainder = dividend % divisor//number := 10//number2 := 1//return number,number2 	//方式1,写返回变量return	//方式2 ，不写返回变量
}//匿名函数方法，作为入参
func proc(input string, processor func(str string)){processor(input)
}//闭包发生器，返回一个闭包
func createCounter(initial int) func() int{if initial < 0{initial = 0}return func()int{initial++return initial}
}//接口声明
type Tank interface {Walk()Fire()
}type Plane interface {Fly()
}//接口和嵌套
type PlaneTank interface {TankPlane
}type Cat interface {CatchMouse()
}type Dog interface {Bark()
}type CatDog struct {Name string
}func (catDog *CatDog)CatchMouse(){fmt.Printf("I am %v CatchMouse\n",catDog.Name)
}func (catDog *CatDog)Bark(){fmt.Printf("I am %v Bark\n",catDog.Name)
}type Printer interface {Print(interface{})
}//定义类型
type FuncCaller func(p interface{})
func (FuncCaller FuncCaller) Print(p interface{}){FuncCaller(p)
}type Person struct {Name stringBrith stringID int64
}func struct_test(){//声明实例化var xm Personxm.Name = "xiaoming"xm.Brith = "1995-08-09"xm.ID = 4402200000000//new函数实例化zw := new(Person)zw.Name = "zhangwei"zw.Brith = ""//取址实例化ww := &Person{}ww.Name = "wanwu"//初始化1sb := Person{Name: "",Brith: "",ID: 777,}sb.ID += 1sd := &Person{"沙雕","1995-4-3",666,}fmt.Print(sd)sd.changeName("新的名字")sd.printMesg("打印")var myDog CatDogmyDog.Name = "xiaogou"myDog.CatchMouse()myDog.Bark()
}//指针接收器，操作的是原来的内存
func (person *Person)changeName(name string){person.Name = namefmt.Printf("My name is %v\n",person.Name)
}//非指针接收器,操作的是拷贝的内存
func(person Person)printMesg(name string){person.Name = namefmt.Printf("My name is %v\n",person.Name)
}//内嵌和组合
type Wheel struct {shape string
}type Car struct {Wheel 	//直接定义类型，不定义对象Name string
}func main() {fmt.Printf("Main running...\n")//pack_flag_test()//pack_point_operate()//pack_alias_test()//if_switch_test("DD",22)//container_test()/*ret1,ret2 := div_func_test(20,3)fmt.Printf("ret1:%v, ret2:%v\n",ret1,ret2)*///匿名函数方法1func (name string){fmt.Printf("My name is %s\n",name)}("zz")//匿名函数方法2currentTime := func(){fmt.Println(time.Now())}currentTime()//匿名函数方法3,函数参数proc("皮皮",func (str string){for _,v := range str{fmt.Printf("%c\n",v)}})c1 := createCounter(1)fmt.Println(c1())fmt.Println(c1())c2 := createCounter(10)fmt.Println(c2())fmt.Println(c1())//复杂的亚比var printer Printer//将匿名函数强转为 FuncCaller赋值给printerprinter = FuncCaller(func(p interface{}){fmt.Println(p)})printer.Print("Golang is good!")struct_test()car := &Car{Wheel{"圆形的",},"福特",}fmt.Println(car.Name,car.shape,"")
}