How to check if character is a letter in Javascript?

Question

I am extracting a character in a Javascript string with:

var first = str.charAt(0);

and I would like to check whether it is a letter. Stran

Answer 1

We can check also in simple way as:

function isLetter(char){
    return ( (char >= 'A' &&  char <= 'Z') ||
             (char >= 'a' &&  char <= 'z') );
}


console.log(isLetter("a"));
console.log(isLetter(3));
console.log(isLetter("H"));