Golang React JS Technology Blog

How to check UPPERCASE characters in a string in Golang?

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

Use strings.ToUpper(s) to check are characters are in uppercase 
package main

import (
	"fmt"
	"strings"
)

func main() {
	s := "UPPERCASE"
	fmt.Println(strings.ToUpper(s) == s) // true

	s = "CAN'T"
	fmt.Println(strings.ToUpper(s) == s) // true
}
Use unicode.IsUpper(s) to verify all characters are in uppercase 
package main

import (
	"fmt"
	"unicode"
)

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

func main() {
	fmt.Println(IsUpper("UPPERCASE")) // true
	fmt.Println(IsUpper("CAN'T"))     // true
}
Most Helpful This Week
How to verify a string only contains letters, numbers, underscores, and dashes in Golang? How to check if a string contains only letters in Golang? How to check if a string contains a numbers in Golang? How to remove all line breaks from a string in Golang? How to check if a string contains a white space in Golang? How to check if a string contains a substring in Golang?