How to convert a slice of bytes in lowercase in Golang?

In Go language slice is more powerful, flexible, convenient than an array, and is a lightweight data structure. The slice is a variable-length sequence which stores elements of a similar type, you are not allowed to store different type of elements in the same slice.
In the Go slice of bytes, you are allowed to convert a slice in the lowercase using ToLower() function. This function returns a copy of the given slice of bytes(treat as UTF-8-encoded bytes) in which all the Unicode letters mapped into lowercase. It is defined under the bytes package so, you have to import bytes package in your program for accessing ToLower function.


func ToLower(slice_1 []byte) []byte

Here, slice_1 represents a slice of bytes which you want to convert to lowercase.






// Go program to illustrate how to convert
// the case of the given slice into lowercase
package main
import (
// Main function
func main() {
    // Creating and initializing 
    // the slice of bytes
    // Using shorthand declaration
    slice_1 := []byte{'G', 'E', 'E', 'K', 'S'}
    slice_2 := []byte{'A', 'P', 'P', 'L', 'E'}
    //Displaying slices
    fmt.Println("Original slice:")
    fmt.Printf("Slice 1: %s", slice_1)
    fmt.Printf("\nSlice 2: %s", slice_2)
    // Converting the elements of the
    // given slices into lowercase
    // Using ToLower function
    res1 := bytes.ToLower(slice_1)
    res2 := bytes.ToLower(slice_2)
    res3 := bytes.ToLower([]byte("GEEKSFORGEEKS"))
    res4 := bytes.ToLower([]byte("GeeKSFORGeeKS"))
    // Display the results
    fmt.Printf("\n\nNew Slice:")
    fmt.Printf("\nSlice 1: %s", res1)
    fmt.Printf("\nSlice 2: %s", res2)
    fmt.Printf("\nSlice 3: %s", res3)
    fmt.Printf("\nSlice 4: %s", res4)



Original slice:
Slice 1: GEEKS
Slice 2: APPLE

New Slice:
Slice 1: geeks
Slice 2: apple
Slice 3: geeksforgeeks
Slice 4: geeksforgeeks

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