我正在创建一个网页,其中我有一个输入文本字段,我想只允许数字字符,如(0,1,2,3,4,5…9)0-9。

我如何使用jQuery做到这一点?


当前回答

这是我用来验证整数或浮点值的数字输入(不显眼的jQuery风格):

$('input[name="number"]').keyup(function(e) { var float = parseFloat($(this).attr('data-float')); /* 2 regexp for validating integer and float inputs ***** > integer_regexp : allow numbers, but do not allow leading zeros > float_regexp : allow numbers + only one dot sign (and only in the middle of the string), but do not allow leading zeros in the integer part *************************************************************************/ var integer_regexp = (/[^0-9]|^0+(?!$)/g); var float_regexp = (/[^0-9\.]|^\.+(?!$)|^0+(?=[0-9]+)|\.(?=\.|.+\.)/g); var regexp = (float % 1 === 0) ? integer_regexp : float_regexp; if (regexp.test(this.value)) { this.value = this.value.replace(regexp, ''); } }); <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <input type="text" data-float="1" id="number" name="number" placeholder="integer"> <input type="text" data-float="0.1" id="number" name="number" placeholder="float">

其他回答

$(document).on("keypress", ".classname", function(evt) {
    evt = (evt) ? evt : window.event;
    var charCode = (evt.which) ? evt.which : evt.keyCode;
    if (charCode > 31 && (charCode < 48 || charCode > 57)) {
        return false;
    }
    return true;
});

这将在添加非数字字符时保持先前的值。

$(document).on('input', '.digit-input', function() {
    var prevVal = $(this).attr('ov') ? $(this).attr('ov') : '';
    var newVal = this.value.replace(/[^0-9]/g, '');
    this.value = newVal != '' ? newVal : prevVal;
    $(this).attr('ov', this.value);
});

$(文件)。据(’input’'。digit-input',函数(){ var prevVal = $(this).attr('ov') ?$(this).attr('ov'): "; var newVal = this.value。回想起(^ [0 - 9]/ g '); this。= = " ? "newVal: prevVal; $ (this)。attr(’ov’this.value); }); < script " src = " https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js " > / < script > <input type="text" class=" digital -input">

在输入文本中放入一个类,并将其命名为only_numbers

把jquery代码放在页面中

$(document).ready(function() {
    $('.only_numbers').keyup(function() {
        var numbers = $(this).val();
        $(this).val(numbers.replace(/\D/, ''));
    });
});

玩得开心:-)

/**
Makes the textbox to accept only numeric input
*/

(function($) {
    $.fn.allowOnlyNumeric = function() {

        /**
        The interval code is commented as every 250 ms onchange of the textbox gets fired.
        */

        //  var createDelegate = function(context, method) {
        //      return function() { method.apply(context, arguments); };
        //  };

        /**
        Checks whether the key is only numeric.
        */
        var isValid = function(key) {
            var validChars = "0123456789";
            var validChar = validChars.indexOf(key) != -1;
            return validChar;
        };

        /**
        Fires the key down event to prevent the control and alt keys
        */
        var keydown = function(evt) {
            if (evt.ctrlKey || evt.altKey) {
                evt.preventDefault();
            }
        };

        /**
        Fires the key press of the text box   
        */
        var keypress = function(evt) {
            var scanCode;
            //scanCode = evt.which;
            if (evt.charCode) { //For ff
                scanCode = evt.charCode;
            }
            else { //For ie
                scanCode = evt.keyCode;
            }

            if (scanCode && scanCode >= 0x20 /* space */) {
                var c = String.fromCharCode(scanCode);
                if (!isValid(c)) {
                    evt.preventDefault();
                }
            }
        };

        /**
        Fires the lost focus event of the textbox   
        */
        var onchange = function() {
            var result = [];
            var enteredText = $(this).val();
            for (var i = 0; i < enteredText.length; i++) {
                var ch = enteredText.substring(i, i + 1);
                if (isValid(ch)) {
                    result.push(ch);
                }
            }
            var resultString = result.join('');
            if (enteredText != resultString) {
                $(this).val(resultString);
            }

        };

        //var _filterInterval = 250;
        //var _intervalID = null;

        //var _intervalHandler = null;

        /**
        Dispose of the textbox to unbind the events.
        */
        this.dispose = function() {
            $(this).die('change', onchange);
            $(this).die('keypress', keypress);
            $(this).die('keydown', keydown);
            //window.clearInterval(_intervalHandler);
        };

        $(this).live('change', onchange);
        $(this).live('keypress', keypress);
        $(this).live('keydown', keydown);
        //_intervalHandler = createDelegate(this, onchange);
        //_intervalID = window.setInterval(_intervalHandler, _filterInterval);
    }
})(jQuery);

上面的$ plugin是从AjaxControlToolkit过滤器文本框extender.js编写的。

然而,有一个行为并没有从AjaxControlToolkit中借用,那就是当用户复制和粘贴任何非数字值时,onchange事件就会触发,文本框就会吞噬这些值。我检查了代码,发现这个onchange在每250ms之后被调用,这是一个性能打击,因此注释了这部分。

function validate_profile(frmid) {
    var form = $('#' + frmid);
    var error = $('.alert-danger', form);
    var success = $('.alert-success', form);
    form.validate({
        errorElement: 'span', //default input error message container
        errorClass: 'help-block', // default input error message class
        focusInvalid: true, // do not focus the last invalid input
        ignore: "",
        rules: {
            contact_no: {
                required: true,
                minlength: 10,
                maxlength: 10,
                number: true
            }, email_id: {
                required: true,
                email: true
            }
        },
        invalidHandler: function (event, validator) { //display error alert on form submit   
            success.hide();
            error.show();
            Metronic.scrollTo(error, -7000);
        },
        highlight: function (element) { // hightlight error inputs
            $(element)
                    .closest('.form-group').addClass('has-error'); // un set error class to the control group
            $(element)
                    .closest('.form-group').removeClass('has-success'); // set success class to the control group
        },
        unhighlight: function (element) { // revert the change done by hightlight
            $(element)
                    .closest('.form-group').removeClass('has-error'); // un set error class to the control group
            $(element)
                    .closest('.form-group').addClass('has-success'); // set success class to the control group
            error.hide();
        },
        success: function (label) {
            label.closest('.form-group').removeClass('has-error');
            label.closest('.form-group').addClass('has-success');
        },
        submitHandler: function (form) {
            success.show();
            error.hide();
            form.submit();
        }
    });
}