如何查找类型是否为float64

Question

I am trying to find if a variable is of type float64:

package main
import ("fmt")
func main() {
    myvar := 12.34
    if myvar.(type) == float64 { 
        fmt.Println("Type is float64.")
    }
}

However, it is not working and giving following error:

./rnFindType.go:6:10: use of .(type) outside type switch
./rnFindType.go:6:21: type float64 is not an expression

What is the problem and how can it be solved?

Answer 1

You know that myvar is a float64 because the variable is declared with the concrete type float64.

If myvar is an interface type, then you can use a type assertion to determine if the concrete value is some type.

var myvar interface{} = 12.34
if _, ok := myvar.(float64); ok {
    fmt.Println("Type is float64.")
}

Try this program at https://play.golang.org/p/n5ftbp5V2Sx