I'm quite new in coding, so might be an easy question for you all. What exactly should I do if I have this array and want to just show the first letter of every element of it?
var friends = ["John", "Will", "Mike"];
I wanted to do it with substr method but I just want to know how to do it with a string.
Use Array.map() to iterate the array, take the 1st letter using destructuring, and return it:
const friends = ["John", "Will", "Mike"];
const result = friends.map(([v])=> v);
console.log(result);As everyone else is using new fancy ECMAScript6 I'll give the oldschool version of it:
var friends = ["John", "Will", "Mike"];
for (var i = 0; i < friends.length; i++) {
console.log(friends[i][0]);
}Use loop for that array and access the first character using charAt(0)
var friends = ["John", "Will", "Mike"];
friends.forEach((name)=>{
console.log(name.charAt(0));
});charAt() method returns a new string consisting of the single UTF-16 code unit located at the specified offset into the string.
Know something about Array.prototype.map
var friends = ["John", "Will", "Mike"];
console.log(friends.map(v=>v[0]))You can use .map() to create array of first letters like:
let firstLetters = friends.map(s => s[0]);
Demo:
let friends = ["John", "Will", "Mike"];
let firstLetters = friends.map(s => s[0]);
console.log(firstLetters);Alternatively you can use String's .charAt() method:
let firstLetters = friends.map(s => s.charAt(0));
Demo:
let friends = ["John", "Will", "Mike"];
let firstLetters = friends.map(s => s.charAt(0));
console.log(firstLetters);Docs:
string.length - 1 as index. For example friends.map(s => s[s.length - 1]); or with charAt() like friends.map(s => s.charAt(s.length - 1);