golang中的断言简单使用

//普通断言
package main

import (
    "fmt"
)

func main() {
    var s string
    s = "str"
    Strerface(s)
}

func Strerface(a interface{})  {
    b, ok := a.(string)
    //ok返回的是一个布尔值
    if ok {
        fmt.Printf("a is string: %s, type: %T\n", b, b)
    }
}

//结合函数和判断
package main

import (
    "fmt"
)

func main() {
    var num float64
    num = 10.33
    showType(num)
}

func showType(any interface{}) {
    switch any.(type) {
    case int:
        fmt.Println("the type of a is int")
    case string:
        fmt.Println("the type of a is string")
    case float64:
        fmt.Println("the type of a is float")
    default:
        fmt.Println("unknown type")
    }
}