添加另一个使用的答案switch......那里有更全面的例子，但这会给你这个想法。
例如，t成为每个case范围内的指定数据类型。请注意，您必须case在一个类型中仅提供一种类型，否则t仍然是interface.
package main
import "fmt"
func main() {
var val interface{} // your starting value
val = 4
var i int // your final value
switch t := val.(type) {
case int:
fmt.Printf("%d == %T\n", t, t)
i = t
case int8:
fmt.Printf("%d == %T\n", t, t)
i = int(t) // standardizes across systems
case int16:
fmt.Printf("%d == %T\n", t, t)
i = int(t) // standardizes across systems
case int32:
fmt.Printf("%d == %T\n", t, t)
i = int(t) // standardizes across systems
case int64:
fmt.Printf("%d == %T\n", t, t)
i = int(t) // standardizes across systems
case bool:
fmt.Printf("%t == %T\n", t, t)
// // not covertible unless...
// if t {
// i = 1
// } else {
// i = 0
// }
case float32:
fmt.Printf("%g == %T\n", t, t)
i = int(t) // standardizes across systems
case float64:
fmt.Printf("%f == %T\n", t, t)
i = int(t) // standardizes across systems
case uint8:
fmt.Printf("%d == %T\n", t, t)
i = int(t) // standardizes across systems
case uint16:
fmt.Printf("%d == %T\n", t, t)
i = int(t) // standardizes across systems
case uint32:
fmt.Printf("%d == %T\n", t, t)
i = int(t) // standardizes across systems
case uint64:
fmt.Printf("%d == %T\n", t, t)
i = int(t) // standardizes across systems
case string:
fmt.Printf("%s == %T\n", t, t)
// gets a little messy...
default:
// what is it then?
fmt.Printf("%v == %T\n", t, t)
}
fmt.Printf("i == %d\n", i)
}