How to check types of value in Go?

Info

Simple ways to check types in golang. The last one with swtich statement is the most useful for complex types.

Using the fmt package

package main

import "fmt"

func main() {
    x := 10
    fmt.Printf("Type of x is %T\n", x) // Output: Type of x is int
}

Using reflect package

package main
import (
    "fmt"
    "reflect"
)
func main() {
    x := 10
    fmt.Println(reflect.TypeOf(x)) // Output: int
}

Using type assertions

package main

import "fmt"

func main() {
    var i interface{} = "hello"

    if s, ok := i.(string); ok {
        fmt.Println("i is a string:", s)
    } else {
        fmt.Println("i is not a string")
    }
}

Using switch statement

package main

import "fmt"

func main() {
    var i interface{} = 10

    switch i.(type) {
    case int:
        fmt.Println("i is an int")
    case string:
        fmt.Println("i is a string")
    default:
        fmt.Println("i is of unknown type")
    }
}