在AngularJS中使用范围和数字输入进行双向绑定

时间:2013-02-27 15:35:36

标签: angularjs

我刚刚开始使用AngularJS并尝试理解绑定技术。对于初学者,我试图制作一个简单的转换计算器(数十件,件数到几十件)。这很有效,但当我尝试将范围输入和数字输入绑定到同一模型属性时,数字输入不会更新调整范围值时。我有一个jsfiddle显示行为:

破解和工作小提琴的常见javascript:

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

myApp.controller('CalcCtrl', function ($scope) {
    var num = 0.0;
    $scope.qty = new Quantity(12);
    $scope.num = num;
});

function Quantity(numOfPcs) {
    var qty = numOfPcs;
    var dozens = numOfPcs / 12;

    this.__defineGetter__("qty", function () {
        return qty;
    });

    this.__defineSetter__("qty", function (val) {
        qty = val;
        dozens = val / 12;
    });

    this.__defineGetter__("dozens", function () {
        return dozens;
    });

    this.__defineSetter__("dozens", function (val) {
        dozens = val;
        qty = val * 12;
    });
}

BROKEN FIDDLE

HTML:

<div ng-controller="CalcCtrl">
    <form>
        <label for="pcs">Pieces:</label>
        <input type="number" min="0" ng-model="qty.qty" size="20" id="pcs"
        />
        <input type="range" min="0" max="100" ng-model="qty.qty" />
        <br/>
        <label for="numOfDozens">Dozens</label>
        <input type="number" min="0" ng-model="qty.dozens" size="20"
        id="numOfDozens" />
    </form>
</div>

但是,将两个数字输入绑定到同一个模型属性似乎可以正常工作,如下所示:

WORKING FIDDLE

HTML:

<div ng-controller="CalcCtrl">
    <form>
        <label for="pcs">Pieces:</label>
        <input type="number" min="0" ng-model="qty.qty" size="20" id="pcs"
        />
        <input type="number" min="0" max="100" ng-model="qty.qty" />
        <br/>
        <label for="numOfDozens">Dozens</label>
        <input type="number" min="0" ng-model="qty.dozens" size="20"
        id="numOfDozens" />
    </form>
</div>

如何将范围数字输入绑定到AngularJS中的单个模型属性?感谢。

3 个答案:

答案 0 :(得分:17)

这里的问题是输入类型=“范围”适用于字符串而不适用​​于数字(而输入类型=“数字”仅适用于数字)。

http://www.w3.org/wiki/HTML/Elements/input/range

  

范围状态表示用于将元素的值设置为的控件   表示数字的字符串。

如果您在val = parseInt(val) setter上添加qty作为第一条指令,它应该有效:

this.__defineSetter__("qty", function (val) {        
    val = parseInt(val);
    qty = val;
    dozens = val / 12;
});

jsfiddle http://jsfiddle.net/bmleite/2Pk3M/2/

答案 1 :(得分:7)

我认为这个解决方案更通用。

myApp.directive('input', function() {
return {
    restrict: 'E',
    require: '?ngModel',
    link: function(scope, element, attrs, ngModel) {
        if ('type' in attrs && attrs.type.toLowerCase() === 'range') {
            ngModel.$parsers.push(parseFloat);
        }
    }
};

});

full explanation

答案 2 :(得分:0)

您可以使用ng-model-options解决此问题。我更改了jsfiddle,这是代码:

<强> HTML

<div ng-controller="CalcCtrl">
    <form>
        <label for="pcs">Pieces:</label>
        <input type="number" min="0" ng-model="qty.qty" size="20" id="pcs" ng-model-options="{ getterSetter: true }"/>
        <input type="range" min="0" max="100" ng-model="qty.qty" ng-model-options="{ getterSetter: true }"/>
        <br/>
        <label for="numOfDozens">Dozens</label>
        <input type="number" min="0" ng-model="qty.dozens" size="20"
        id="numOfDozens" ng-model-options="{ getterSetter: true }"/>
    </form>
</div>

<强> JS

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

myApp.controller('CalcCtrl', function ($scope) {
    var num = 1.0;
    $scope.qty = {
    qty:function (val) {
        return arguments.length ? (num = parseFloat(val)) : num;
     }, 
     dozens: function (val) {
            return arguments.length ? (num = val*12) : num/12;
        }
     };
});