How to convert String to String array in Kotlin?

Question

I want to know how I can convert one string or a String Object in a String array using kotlin.

I made some research and found this JAVA code which seems to do what I need.

public static void main(String[] args) { 
String word="abc";
        String[] array = new String[word.length()];
        for(int i = 0; i < word.length(); i++)
        {
            array[i] = String.valueOf(word.charAt(i));
        }

        for(String a:array){
            System.out.println(a);
        }
}

I expect to have something like this or better than it in Kotlin.

Thanks in advance.

Well, it's complicated. Java sample is incorrect, thus, direct translations to Kotlin are incorrect, too. The problem is that `char` is not a character or code point but a UTF-16 word which can represent a half of a code point. See https://stackoverflow.com/questions/40878804/how-to-count-grapheme-clusters-or-perceived-emoji-characters-in-java, and use builtin IntelliJ J2K converter. — Miha_x64, Sep 26 '19 at 15:36

score 12 · Accepted Answer · answered Sep 26 '19 at 15:21

12

Something like this:

val str = "abcd"
val array: Array<String> = str.toCharArray().map { it.toString() }.toTypedArray()

answered Sep 26 '19 at 15:21

Artem Botnev

2,267
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19

9

A bit simpler: `str.map { it.toString() }.toTypedArray()` – David Soroko Sep 26 '19 at 19:11
You can also simply allocate the result to a string list like this:`val listStr: List = str.map { it.toString() }` – Kenneth Murerwa Sep 10 '21 at 05:40

francis · Answer 2 · 2021-03-09T23:45:53.323

8

Try This:

val str = "Hello"
val arr = str.split("")

fun main() {
    println(arr) // [, H, e, l, l, o]
}

edited Mar 09 '21 at 23:45

answered Mar 09 '21 at 22:45

francis

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String.split("") returns a List, but the question is about Array. – raianmr Jan 11 '23 at 16:11
1

You can append `.toTypedArray()` to convert list to array – francis Jan 11 '23 at 19:14

score 5 · Answer 3 · answered Sep 26 '19 at 15:22

5

You can fill an array as you initialize it using a lambda that takes the index as an argument.

fun main() {
    val word = "abcd"
    val array = Array(word.length) {word[it].toString()}
    array.forEach { println(it) }
}

answered Sep 26 '19 at 15:22

Tenfour04

83,111
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score 1 · Answer 4 · answered Sep 26 '19 at 15:55

1

You can use java.text.BreakIterator both from Java and Kotlin-JVM to iterate through 'grapheme clusters', i. e. user-visible 'characters'.

answered Sep 26 '19 at 15:55

Miha_x64

5,973
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Rinat Suleimanov · Answer 5 · 2020-04-16T23:44:20.140

1

fun main() {
    val string = "Hello"
    val array = Array(string.length) { string[it].toString() }
}

edited Apr 16 '20 at 23:44

answered Sep 26 '19 at 18:59

Rinat Suleimanov

517
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How to convert String to String array in Kotlin?

5 Answers5