货币角度筛选器，允许输入负数

Question

我有一个指令，通过添加小数点作为用户类型来过滤货币。

我的问题是它不允许有负面影响。如果允许用户输入一个“-”符号，并让它始终出现在数字的开头，或者键入a '+‘并让它消失，那就太好了。

需要：

1. 将十进制字段格式化为用户类型
2. 字段必须是数字。
3. 必须允许负数-
4. 允许0.00作为数字输入

看看我的柱塞。它有input = number，但不允许负数：

app.directive('format', ['$filter', function ($filter) {
    return {
        require: 'ngModel', //there must be ng-model in the html
        link: function (scope, elem, attr, ctrl) {
            if (!ctrl) return;

            ctrl.$parsers.unshift(function (viewValue, modelValue) {
                var plainNumber = viewValue.replace(/[^-+0-9]/g,'');

                // use angular internal 'number' filter
                plainNumber = $filter('number')(plainNumber / 100, 2).replace(/,/g, '');

                // update the $viewValue
                ctrl.$setViewValue(plainNumber);

                // reflect on the DOM element
                ctrl.$render();

                // return the modified value to next parser
                return plainNumber;
            });
        }
    };
}]);

Answer 1

这将完成您希望它做的事情：

var app = angular.module('App',[]);

 app.controller('MainCtrl', function ($scope) {


});

 app.directive('format', ['$filter', function ($filter) {
 return {
            require: 'ngModel', //there must be ng-model in the html
            link: function (scope, elem, attr, ctrl) {
                if (!ctrl) return;

                ctrl.$parsers.unshift(function (viewValue, modelValue) {
                    var plainNumber = viewValue.replace(/[^-+0-9]/g,'');
                    var newVal = plainNumber.charAt(plainNumber.length-1);
                    var positive = plainNumber.charAt(0) != '-';
                    if(isNaN(plainNumber.charAt(plainNumber.length-1))){
                      plainNumber = plainNumber.substr(0,plainNumber.length-1)
                    }
                    //use angular internal 'number' filter
                    plainNumber = $filter('number')(plainNumber / 100, 2).replace(/,/g, '');
                    if(positive && newVal == '-'){
                      plainNumber = '-' + plainNumber;
                    }
                    else if(!positive && newVal == '+'){
                      plainNumber = plainNumber.substr(1);
                    }
                    plainNumber.replace('.', ',');
                    //update the $viewValue
                    ctrl.$setViewValue(plainNumber);
                    //reflect on the DOM element
                    ctrl.$render();
                    //return the modified value to next parser
                    return plainNumber;
                });
            }
        };

}]);

只需从以下位置删除type="number“：

<input ng-model="amount" format="number" />