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Golang unicode.IsNumber() Function with Examples

Golang | unicode.IsNumber() Function: Here, we are going to learn about the IsNumber() function of the unicode package with its usages, syntax, and examples.
Submitted by IncludeHelp, on September 17, 2021

unicode.IsNumber()

The IsNumber() function is an inbuilt function of the unicode package which is used to check whether the given r rune is a number (category N – the set of Unicode number character).

It accepts one parameter (r rune) and returns true if rune r is a number character; false, otherwise.

Syntax:

func IsNumber(r rune) bool

Parameter(s):

• r : Rune type value to be checked whether it is a number character or not.

Return Value:

The return type of the unicode.IsNumber() function is a bool, it returns true if rune r is a number character; false, otherwise.

Example 1:

// Golang program to demonstrate the
// example of unicode.IsNumber() Function

package main

import (
	"fmt"
	"unicode"
)

func main() {
	fmt.Println("unicode.IsNumber('1'):",
		unicode.IsNumber('1'))
	fmt.Println("unicode.IsNumber('9'):",
		unicode.IsNumber('9'))
	fmt.Println("unicode.IsNumber('Ⅱ'):",
		unicode.IsNumber('Ⅱ'))
	fmt.Println("unicode.IsNumber('Ⅻ'):",
		unicode.IsNumber('Ⅻ'))
	fmt.Println("unicode.IsNumber('ⅱ')",
		unicode.IsNumber('ⅱ'))
	fmt.Println("unicode.IsNumber('ⅻ'):",
		unicode.IsNumber('ⅻ'))
	fmt.Println("unicode.IsNumber('g'):",
		unicode.IsNumber('g'))
}

Output:

unicode.IsNumber('1'): true
unicode.IsNumber('9'): true
unicode.IsNumber('Ⅱ'): true
unicode.IsNumber('Ⅻ'): true
unicode.IsNumber('ⅱ') true
unicode.IsNumber('ⅻ'): true
unicode.IsNumber('g'): false

Example 2:

// Golang program to demonstrate the
// example of unicode.IsNumber() Function

package main

import (
	"fmt"
	"unicode"
)

func main() {
	var r rune
	var result bool

	r = 'ⅻ'
	result = unicode.IsNumber(r)
	if result == true {
		fmt.Printf("%c is a number character.\n", r)
	} else {
		fmt.Printf("%c is not a number character.\n", r)
	}

	r = '8'
	result = unicode.IsNumber(r)
	if result == true {
		fmt.Printf("%c is a number character.\n", r)
	} else {
		fmt.Printf("%c is not a number character.\n", r)
	}

	r = 'Q'
	result = unicode.IsNumber(r)
	if result == true {
		fmt.Printf("%c is a number character.\n", r)
	} else {
		fmt.Printf("%c is not a number character.\n", r)
	}
}

Output:

ⅻ is a number character.
8 is a number character.
Q is not a number character.

Golang unicode Package »

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