Only Alphabet | Only Number | No Special Character - Textboxes Javascript Keypress Code

Many times we need code urgently and we think about a place from where we can just copy & paste. This post is one of them. Here you can find code and working example of javascript code to restrict user input in textboxes. We are providing you with 4 types of textboxes and there's a link in the bottom from where you can get all the keycodes and adjust our JavaScript code as per your need if you want.

Only Alphabets Allowed Textbox:

Code:

function onlyAlphabets(e, t) {
    try {
        if (window.event) {
            var charCode = window.event.keyCode;
        }
        else if (e) {
            var charCode = e.which;
        }
        else { return true; }
        if ((charCode > 64 && charCode < 91) || (charCode > 96 && charCode < 123))
            return true;
        else
            return false;
    }
    catch (err) {
        alert(err.Description);
    }
}
//textbox's html

Only Number Allowed Textbox:

Code:

function onlyNumber(e, t) {
    try {
        if (window.event) {
            var charCode = window.event.keyCode;
        }
        else if (e) {
            var charCode = e.which;
        }
        else { return true; }
        if (charCode > 31 && (charCode < 48 || charCode > 57))
            return false;
        else
            return true;
    }
    catch (err) {
        alert(err.Description);
    }
}
//textbox's html

No Special Characters Allowed, Just Alphabets & Numbers

Code:

function noSpecialCharacters(e, t) {
    try {
        if (window.event) {
            var charCode = window.event.keyCode;
        }
        else if (e) {
            var charCode = e.which;
        }
        else { return true; }
        if (charCode < 48 || (charCode > 57 && charCode < 65) || (charCode > 90 && charCode < 97) || charCode > 122)
            return false;
        else
            return true;
    }
    catch (err) {
        alert(err.Description);
    }
}
//textbox's html

No Special Characters Allowed, Just Alphabets & Numbers - With Spacebar

Code:

function noSpecialCharactersPlusSpace(e, t) {
    try {
        if (window.event) {
            var charCode = window.event.keyCode;
        }
        else if (e) {
            var charCode = e.which;
        }
        else { return true; }
        if ((charCode < 48 && charCode != 32) || (charCode > 57 && charCode < 65) || (charCode > 90 && charCode < 97) || charCode > 122)
            return false;
        else
            return true;
    }
    catch (err) {
        alert(err.Description);
    }
}
//textbox's html

However, the world is so big and everyone has their own requirements. So you can tweak this code just to suit your requirements. In keypress events we are just restricting user input on the basis of the key they pressed.

Here's a reference list of all the keycodes W3Schools Link.

Let us know for any help. We would be happy to help.