Determine if a Letter or a number was pressed - Javascript [duplicate]

Question

So I know that we can find if a key was pressed, and we can know which key was pressed by using javascript.

To determine if a key was down or pressed we can just use jQuery

$( "#some id" ).keydown(function() 

or

$( "#m" ).keypress(function() 

But this does not work pretty good for me. I am trying to determine if a letter, or a number were pressed.

BUT, to be efficient, I don't want to check with a big if (or a for loop, worse) whether the key pressed was a letter or a character(by comparing and checking the character code)

Is there like a built in javascript function that determines if a number was pressed or a letter was pressed? is there an efficient way of doing this? or I am just overcomplicating things?

Answer 1

Simply check the range:

if (event.keyCode >= 48 && event.keyCode <= 57) {
    // Number
} else if (event.keyCode >= 65 && event.keyCode <= 90) {
    // Alphabet upper case
} else if (event.keyCode >= 97 && event.keyCode <= 122) {
    // Alphabet lower case
}

Here is a detailed answer to a similar question. Good reference.

The Number pad code is the same as that above the keyboard: Reference from Keyboard Keys and Key Code Values

---

UPDATE:

Use the .key

var x = event.key; // instead of event.keyCode

and

if (x >= 48 && x <= 57) {
    // Number
} else if (x >= 65 && x <= 90) {
    // Alphabet upper case
} else if (x >= 97 && x <= 122) {
    // Alphabet lower case
}