go 变量篇

go 变量篇

package main

import "fmt"

func main() {
	//1.声明单个变量  var name type
	var age int
	fmt.Println("hello world", age)
	age = 28
	fmt.Println("hello world", age)
	age = 54
	fmt.Println("hello world", age)

	//2.声明变量并初始化  var name type = initialvalue
	var name string = "张三"
	fmt.Println("name: ", name)

	//3.类型推断 如果变量有初始值，可以根据变量的值，自动推断出变量的类型，可以省略变量类型的书写
	var sex = 1
	fmt.Println("sex: ", sex)

	//4.声明多个变量
	//var name1,name2 type = ini11,init2
	var height, weight = 175, 60
	fmt.Println("height: ", height, "weight: ", weight)

	//定义 但是没有初始化
	var height2, weight2 int
	fmt.Println("height2: ", height2, "weight2: ", weight2)
	//对变量进行赋值
	height2 = 170
	weight2 = 80
	fmt.Println("height2: ", height2, "weight2: ", weight2)

	//5.在语句中申明不同的变量  var (
	//   name1=init1
	//   name2=init2
	// )

	var (
		color = "红色" //string
		money = 12   //int
	)
	fmt.Println("color: ", color, "money: ", money)

	//6 := 简短的声明变量的形式
	a, b := 10, 20
	fmt.Println("a: ", a, "b: ", b)
	//go中=和:=的区别
	//=是赋值  := 是声明并赋值

}