How to Index Characters in a String in Go

Using individual characters

In UTF-8, ASCII characters are single-byte corresponding to the first 128 Unicode characters. Strings behave like slices of bytes. A rune is an integer value identifying a Unicode code point. For example,

package main

import "fmt"

func main() {
  s := "Hello,世界"
  
  fmt.Println(string(s[1]))
  fmt.Println(string([]rune(s)[6]))
}

e
世

Using strings.Split Function

Split slices s into all substrings separated by sep and returns a slice of the substrings between those separators.

See the following example:

package main

import (
  "fmt"
  "strings"
)

func main() {
  s := "Hello,世界"

  b := strings.Split(s, "")
  fmt.Println(b[6])
}

世

Golang Errors

panic: runtime error: index out of range [9] with length 8:

fmt.Println(b[9])

panic: runtime error: index out of range [9] with length 8
goroutine 1 [running]: