encoding/hex: invalid byte: U+0068 'h' Golang

Question

I'm trying to convert a string into a byte array containing its hexadecimal values, here is the code I've written:

package main

import (
     "encoding/hex"
     "fmt"
     "os"
)

func main() {
     str :="abcdefhijklmnopqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ123456789"

     b, err := hex.DecodeString(str)

     if err != nil {
             fmt.Println(err)
             os.Exit(1)
     }

     fmt.Printf("Decoded bytes %v \n ", b)
}

Here is the link from Go PlayGround: http://play.golang.org/p/8PMEFTCYSd

But it's giving me the error *encoding/hex: invalid byte: U+0068 'h' Golang *. What's the problem here? I want to convert my string into byte array containing hexadecimal values of each character in the string. I want b[n] to contain hexadecimal value of str[n].

Solution 1

I want to convert my string into byte array containing hexadecimal values of each character in the string.

You can simply convert a string to a []byte (byte slice, not exactly the same as array!) by using a simple type conversion:

b := []byte(str)

And you're done!

If you want to print it as a hexadecimal string, you can do that with the fmt.Printf() function using both the string and the []byte:

fmt.Printf("%x", str)
// Or:
fmt.Printf("%x", b)

Tip: you can use the format string "% x" to have a space printed between each of the hexadecimal forms of the bytes/characters:

fmt.Printf("% x", str)

If you want the result of the hexadecimal form as a string, you can use the fmt.Sprintf() variant:

hexst := fmt.Sprintf("%x", str)
// Or:
hexst := fmt.Sprintf("%x", b)

Or as an alternative you can use the hex.EncodeToString() function from the encoding/hex package:

hexst := hex.EncodeToString(b)

Solution 2

Your code is trying to decode from hex. That string is not hex encoded.

To encode to hex try this

b := fmt.Sprintf("%x", str)

fmt.Printf("Decoded bytes %v", []byte(b))