access_individual_characters.md

Access Individual Characters

Given a String, you can access the individual characters which comprise it by using .charAt.

The first character can be accessed by putting 0 in the parentheses. The second by using 1, and so on.

~void main() {
String spy = "loid";

char l = spy.charAt(0);
System.out.println(l);

char o = spy.charAt(1);
System.out.println(o);

char i = spy.charAt(2);
System.out.println(i);

char d = spy.charAt(3);
System.out.println(d);
~}

We call this number the "index" of the character.¹

The index of the character to access can come from a variable.

~void main() {
String assassin = "yor";
int indexOfR = 2;

char r = assassin.charAt(indexOfR);
System.out.println(r);
~}

If you give a number equal to or greater than the length of the String or a number less than zero, you will get an error.

~void main() {
String student = "anya";
// Crash!
student.charAt(999);
~}

~void main() {
String dog = "bond";
// Crash!
dog.charAt(-1);
~}

Footnotes

1. There will be more things which have their individual elements accessible by indexes. They will all generally start from 0 for the first element but there are rare exceptions. ↩