Go语言中的类型断言

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类型断言

类型断言，由于接口是一般类型，不知道具体类型，如果要转成具体类型
可以采用以下方法进行转换：

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func test1() {
	var a interface{}
	var b int = 10
	a = b
	fmt.Printf("a type is %T value is %d\n", a, a)
	// 断言
	c, ok := a.(int)
	if ok == false {
		fmt.Println("conversion fail")
		return
	}
	fmt.Printf("c type is %T value is %d\n", c, c)
}

func main() {
	test1()
}
------------
a type is int value is 10
c type is int value is 10



type Student struct{}

func assertion(item ...interface{}) {
	for i, v := range item {
		switch v.(type) {
		case bool:
			fmt.Printf("%d param is bool value is %v\n", i, v)
		case string:
			fmt.Printf("%d param is string value is %v\n", i, v)
		case float32, float64:
			fmt.Printf("%d param is float value is %v\n", i, v)
		case int, int32, int64:
			fmt.Printf("%d param is int value is %v\n", i, v)
		case Student:
			fmt.Printf("%d param is Student value is %v\n", i, v)
		case *Student:
			fmt.Printf("%d param is Student Pointer value is %v\n", i, v)
		default:
			fmt.Printf("%d param type is unknown value is %v\n", i, v)
		}
	}
}

func test2() {
	var stu Student
	assertion(true, stu, 1, 1.2, "test", &Student{})
}

func main() {
	test2()
}
--------------
0 param is bool value is true
1 param is Student value is {}
2 param is int value is 1
3 param is float value is 1.2
4 param is string value is test
5 param is Student Pointer value is &{}