如何将文本输入仅限制为数字，但允许使用10键输入数字？

Question

I am confused why I am not able to use the 10 key to input numbers.

The following example auto fills the "/". I tried a few different ways to adjust the regex on it, but when I do, I can't backspace or delete anything past the last "/". (01/01/2000 ... 01/01/ <- won't let me delete past this).

       $('#date').keydown(function (e) {
            var key = e.charCode || e.keyCode || 0;
            $date = $(this);

            if (key !== 8) {
                var regex = new RegExp("^[0-9\t/]");
                var key = String.fromCharCode(!event.charCode ? event.which : event.charCode);
                if (!regex.test(key)) {
                   event.preventDefault();
                   return false;
                }

                if ($date.val().length === 0) {
                    $date.val($date.val() + '');
                }
                if ($date.val().length === 2) {
                    $date.val($date.val() + '/');
                }
                if ($date.val().length === 5) {
                    $date.val($date.val() + '/');
                }
            }
        }); 

Please help me find a way where it continues to auto-format the "/" as it does now but restricts to numbers only (except the required "/") and allows me to use the 10 key numbers.

Any help would be greatly appreciated.

Thank you in advance.

Answer 1

if you want allow only number and ignore any key : use this code in JavaScript tag:

 $('*[data-validation="digit"]').keydown(function (e) {
                if ($.inArray(e.keyCode, [46, 8, 9, 27, 13, 110, 190]) !== -1 ||
                        (e.keyCode == 65 && e.ctrlKey === true) ||
                        (e.keyCode >= 35 && e.keyCode <= 40)) {
                    return;
                }
                if ((e.shiftKey || (e.keyCode < 48 || e.keyCode > 57)) && (e.keyCode < 96 || e.keyCode > 105)) {
                    e.preventDefault();
                }
            });

and any input that you want apply this role add this attribute :

data-validation="digit"

for example :

<input data-validation="digit" /> 

I recommend you Use a Masked Input plugin eg: Masked Input plugin for jQuery

for example for date :

 $("#date").mask("99/99/9999",{placeholder:"mm/dd/yyyy"});

in this plugin you can combination of word and number or any characters

Answer 2

You're not checking for backspace properly. Check your value of 'key'.

I think it should assigned as followed:

var key = e.keyCode;

Also, why is half of it e and later on you have event ?

var key = String.fromCharCode(!event.charCode ? event.which : event.charCode);

This might also be useful for JS reference:

https://css-tricks.com/snippets/javascript/javascript-keycodes/

You might also want to use jQuery's which . It should work across browsers.