go | 03 四种变量声明与多变量声明

package main
import "fmt"
//声明全局变量可以 方法一、方法二、方法三；方法四只可用于局部变量
var fullInt = 400
var fullStr =  "全局变量"
func main(){
    //方法一：声明一个变量,默认值为0
    var aInt int
    var aStr string
    fmt.Println("aInt =" , aInt,",aStr =",aStr,"-----")
    //方法二：声明一个变量，初始化一个值
    var bInt int = 100
    var bStr string = "方法二"
    fmt.Println("bInt =",bInt,",bStr =",bStr)
    //方法三：在初始化时，可以省去数据类型，通过值自动匹配当前的数据类型
    var cInt = 200
    var cStr = "方法三"
    fmt.Println("cInt =",cInt,",cStr =",cStr)
    //方法四：省去var，直接用 :=
    dInt := 300
    fmt.Printf("type of dInt = %T\n",dInt)
    dStr := "方法四"
    fmt.Printf("type of dStr = %T\n",dStr)
    dFloat := 3.1415 //float64 8个字节
    fmt.Printf("type of dFloat = %T\n",dFloat)
    dboolean := true
    fmt.Printf("type of dboolean = %T\n",dboolean)
    fmt.Println("dInt =",dInt,",dStr =",dStr,",dFloat =",dFloat,",dboolean =",dboolean)
    //声明多个变量
    var xx,yy int= 2,3
    fmt.Println(xx,"--",yy)
    var zz,aa = 2,"yyz"
    fmt.Println(zz,"--",aa)
    //多行多变量声明
    var(
        x1 int = 2
        x2 string = "x2"
    )
    fmt.Println(x1,"--",x2)
    var(
        y1 = 3
        y2 = true
    )
    fmt.Println(y1,"--",y2)
}