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Golang strings.IndexByte() Function with Examples

Golang | strings.IndexByte() Function: Here, we are going to learn about the IndexByte() function of strings package with its usages, syntax, and examples.
Submitted by IncludeHelp, on August 16, 2021

strings.IndexByte()

The IndexByte() function is an inbuilt function of strings package which is used to get the index of the first occurrence (instance) of a character (byte) in string. It accepts two parameters – string and a character (byte) and returns the index, or -1 if the byte is not present in the string.

Syntax

func IndexByte(str string, chr byte) int

Parameters

• str : String in which we have to check the byte.
• chr : Character (byte) to be checked in the string.

Return Value

The return type of IndexByte() function is a bool, it returns the index of the first occurrence (instance) of character (byte) in the string, or -1 if the character (byte) is not present in the string.

Example 1

// Golang program to demonstrate the
// example of strings.IndexByte() Function

package main

import (
	"fmt"
	"strings"
)

func main() {
	fmt.Println(strings.IndexByte("Hello, world", 'w'))
	fmt.Println(strings.IndexByte("Hello, world", 'x'))
	fmt.Println(strings.IndexByte("Okay@123", '@'))
}

Output:

7
-1
4

Example 2

// Golang program to demonstrate the
// example of strings.IndexByte() Function

package main

import (
	"fmt"
	"strings"
)

func main() {
	var str string
	var chr byte
	var index int

	str = "Hello, world!"
	chr = 'w'

	index = strings.IndexByte(str, chr)
	if index >= 0 {
		fmt.Printf("%c found in %q at %d index.\n", chr, str, index)
	} else {
		fmt.Printf("%c does not found in %q.\n", chr, str)
	}

	str = "Hello, world!"
	chr = 'x'

	index = strings.IndexByte(str, chr)
	if index >= 0 {
		fmt.Printf("%c found in %q at %d index.\n", chr, str, index)
	} else {
		fmt.Printf("%c does not found in %q.\n", chr, str)
	}

	str = "Okay@123"
	chr = '@'

	index = strings.IndexByte(str, chr)
	if index >= 0 {
		fmt.Printf("%c found in %q at %d index.\n", chr, str, index)
	} else {
		fmt.Printf("%c does not found in %q.\n", chr, str)
	}
}

Output:

w found in "Hello, world!" at 7 index.
x does not found in "Hello, world!".
@ found in "Okay@123" at 4 index.

Golang strings Package Functions »

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