go ---switch语句

package main

import (
	"fmt"
)

func main() {

	var ar = [...]string{"A", "B", "D", "E"}

	for _, content := range ar {
		switch content {
		case "A":
			fmt.Println("AAA")
		case "B", "C", "D":
			fmt.Println("BBB")
		default:
			fmt.Println("CCC")
		}

	}

}

　　输出：

AAA

BBB

BBB

CCC

 使用fallthrough，来向下一个case语句转移流程控制权，

package main

import (
	"fmt"
)

func main() {

	var ar = [...]string{"A", "B", "D", "E"}

	for _, content := range ar {
		switch content {
		case "A":
			fallthrough
		case "B", "C", "D":
			fmt.Println("BBB")
		default:
			fmt.Println("CCC")
		}

	}

}

　　输出：

BBB

BBB

BBB

CCC

类型switch语句：对类型进行判定，而不是值

package main

import (
	"fmt"
)

func main() {

	v := 11

	switch i := interface{}(v).(type) {

	case int, int8, int16, int32, int64:

		fmt.Printf("A signed integer: %v. the type is :%T
", v, v)
		fmt.Printf("A signed integer: %v. the type is :%T
", i, i)
	case uint, uint8, uint16, uint32, uint64:

		fmt.Printf("A unsigned integer: %v. the type is :%T
", v, v)
		fmt.Printf("A unsigned integer: %v. the type is :%T
", i, i)

	default:

		fmt.Println("Unknown!")

	}

}

　　输出：

A signed integer: 11. the type is :int

A signed integer: 11. the type is :int

package main

import (
	"fmt"
)

func main() {

	var v interface{}
	v = "hi"

	switch v.(type) {
	case string:
		fmt.Printf("The string is %v 
", v.(string))

	case int, int8, int16, int32, int64:

		fmt.Printf("A signed integer: %v. the type is :%T
", v, v)

	case uint, uint8, uint16, uint32, uint64:

		fmt.Printf("A unsigned integer: %v. the type is :%T
", v, v)

	default:

		fmt.Println("Unknown!")

	}

}

　　输出：

The string is hi