JavaScript String charAt() is a built-in method that returns the character at a specified index within a string. If the index is out of range (i.e., greater than or equal to the string’s length), the method returns an empty string.
Syntax
string.charAt(index)
Parameters
The index parameter is required. It is an integer representing the index of the character you want to return.
Example
let str = 'AppDividend';
let res = str.charAt(5);
console.log(res);
It will return the character to position 5, and the string’s index starts from 0. So it should return 0.
Output
Extracting the first letter of every string in the array
We can extract the first letter of an array by the following code.
const friends = ['Rachel', 'Chandler', 'Ross', 'Phoebe', 'Monica', 'Joey'];
extractedString = friends.map(i => i.charAt(0));
console.log(extractedString);
We have defined one array full of strings. Now, we only need to get the first character from each item.
We map through each element, get the first character, add that character to an array, and return it. Since the map method is a pure function, it will return a new array.
Output
Displaying the characters at different locations in the string
We can show all the characters like this.
let OString = 'appdividend';
console.log("The character at index 0 is '" + OString.charAt(0) + "'");
console.log("The character at index 1 is '" + OString.charAt(1) + "'");
console.log("The character at index 2 is '" + OString.charAt(2) + "'");
console.log("The character at index 3 is '" + OString.charAt(3) + "'");
console.log("The character at index 4 is '" + OString.charAt(4) + "'");
console.log("The character at index 5 is '" + OString.charAt(5) + "'");
console.log("The character at index 6 is '" + OString.charAt(6) + "'");
console.log("The character at index 7 is '" + OString.charAt(7) + "'");
console.log("The character at index 8 is '" + OString.charAt(8) + "'");
console.log("The character at index 9 is '" + OString.charAt(9) + "'");
console.log("The character at index 10 is '" + OString.charAt(10) + "'");
Output
That’s it.