Question

I am working in Javascript. I am trying to make a function on the keypress event. I want to make function for validation on mobile number. I want to allow only digits in it. I also want to allow ctrl+v and ctrl+a in this but I dont want to allow V and A as characters.

I have seen many answers here but no one is purely same.

Answer 1

If you only care that digits are entered, as it seems from your question, this Jquery code will work.

It uses on keyup() and thus it will work on ctrl+v as well. It won’t work if someone uses right-click to paste, and for that reason, you can just disable right clicking on that field.

It works by stripping off the last character of the input value if it is not a number. So if a user enters 25s or 25ss, it will get stripped down to 25.

Live Demo

The Jquery

$(document).ready(function(){
    $('#number').keyup(function(){    
        var input = this.value;
        while (isNaN(input))
        {
            input = input.substring(0,input.length-1);
            $('#number').val(input);             
        }
    });
    //disable right click on the field
    $('#number').bind("contextmenu",function(e){
        return false;
    });
});