How to check lowercase characters in a string in Golang?

Checking if all characters of a string are lowercase evaluates to True or False. For example, checking if the string "test" is lowercase evaluates to True.

Use strings.ToLower(s) to check are characters are in lowercase
package main

import (
	"fmt"
	"strings"
)

func main() {
	s := "lowercase"
	fmt.Println(strings.ToLower(s) == s) // true

	s = "can't say"
	fmt.Println(strings.ToLower(s) == s) // true
}

Use unicode.IsLower(s) to verify all characters are in lowercase
package main

import (
	"fmt"
	"unicode"
)

func IsLower(s string) bool {
	for _, r := range s {
		if !unicode.IsLower(r) && unicode.IsLetter(r) {
			return false
		}
	}
	return true
}

func main() {
	fmt.Println(IsLower("lowercase")) // true
	fmt.Println(IsLower("can't"))     // true
}


Most Helpful This Week