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\n", v, v)
		fmt.Printf("A signed integer: %v. the type is :%T\n", i, i)
	case uint, uint8, uint16, uint32, uint64:
 
		fmt.Printf("A unsigned integer: %v. the type is :%T\n", v, v)
		fmt.Printf("A unsigned integer: %v. the type is :%T\n", 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 \n", v.(string))
 
	case int, int8, int16, int32, int64:
 
		fmt.Printf("A signed integer: %v. the type is :%T\n", v, v)
 
	case uint, uint8, uint16, uint32, uint64:
 
		fmt.Printf("A unsigned integer: %v. the type is :%T\n", v, v)
 
	default:
 
		fmt.Println("Unknown!")
 
	}
 
}

　　输出：

The string is hi