如何使用AngularJS绑定到复选框值列表？

本文翻译自：How do I bind to list of checkbox values with AngularJS?

I have a few checkboxes: 我有几个复选框：

<input type='checkbox' value="apple" checked>
<input type='checkbox' value="orange">
<input type='checkbox' value="pear" checked>
<input type='checkbox' value="naartjie">

That I would like to bind to a list in my controller such that whenever a checkbox is changed the controller maintains a list of all the checked values, for example, ['apple', 'pear'] . 我想绑定到我的控制器中的列表，这样每当复选框被更改时，控制器都会保留所有已检查值的列表，例如['apple', 'pear'] 。

ng-model seems to only be able to bind the value of one single checkbox to a variable in the controller. ng-model似乎只能将一个复选框的值绑定到控制器中的变量。

Is there another way to do it so that I can bind the four checkboxes to a list in the controller? 还有另一种方法可以将四个复选框绑定到控制器中的列表吗？

#1楼

参考：https://stackoom.com/question/ytsD/如何使用AngularJS绑定到复选框值列表

#2楼

I think the easiest workaround would be to use 'select' with 'multiple' specified: 我认为最简单的解决方法是使用'select'并指定'multiple'：

<select ng-model="selectedfruit" multiple ng-options="v for v in fruit"></select>

Otherwise, I think you'll have to process the list to construct the list (by $watch() ing the model array bind with checkboxes). 否则，我认为你必须处理列表来构造列表（通过$watch()模型数组绑定与复选框）。

#3楼

<input type='checkbox' ng-repeat="fruit in fruits"ng-checked="checkedFruits.indexOf(fruit) != -1" ng-click="toggleCheck(fruit)">

. 。

function SomeCtrl ($scope) {$scope.fruits = ["apple, orange, pear, naartjie"];$scope.checkedFruits = [];$scope.toggleCheck = function (fruit) {if ($scope.checkedFruits.indexOf(fruit) === -1) {$scope.checkedFruits.push(fruit);} else {$scope.checkedFruits.splice($scope.checkedFruits.indexOf(fruit), 1);}};
}

#4楼

Here's a quick little reusable directive that seems to do what you're looking to do. 这是一个快速的小型可重用指令，似乎可以做你想做的事情。 I've simply called it checkList . 我简单地称它为checkList 。 It updates the array when the checkboxes change, and updates the checkboxes when the array changes. 它会在复选框更改时更新阵列，并在阵列更改时更新复选框。

app.directive('checkList', function() {return {scope: {list: '=checkList',value: '@'},link: function(scope, elem, attrs) {var handler = function(setup) {var checked = elem.prop('checked');var index = scope.list.indexOf(scope.value);if (checked && index == -1) {if (setup) elem.prop('checked', false);else scope.list.push(scope.value);} else if (!checked && index != -1) {if (setup) elem.prop('checked', true);else scope.list.splice(index, 1);}};var setupHandler = handler.bind(null, true);var changeHandler = handler.bind(null, false);elem.bind('change', function() {scope.$apply(changeHandler);});scope.$watch('list', setupHandler, true);}};
});

Here's a controller and a view that shows how you might go about using it. 这是一个控制器和一个显示如何使用它的视图。

<div ng-app="myApp" ng-controller='MainController'><span ng-repeat="fruit in fruits"><input type='checkbox' value="{{fruit}}" check-list='checked_fruits'> {{fruit}}<br /></span><div>The following fruits are checked: {{checked_fruits | json}}</div><div>Add fruit to the array manually:<button ng-repeat="fruit in fruits" ng-click='addFruit(fruit)'>{{fruit}}</button></div>
</div>

app.controller('MainController', function($scope) {$scope.fruits = ['apple', 'orange', 'pear', 'naartjie'];$scope.checked_fruits = ['apple', 'pear'];$scope.addFruit = function(fruit) {if ($scope.checked_fruits.indexOf(fruit) != -1) return;$scope.checked_fruits.push(fruit);};
});

(The buttons demonstrate that changing the array will also update the checkboxes.) （按钮表明更改阵列也会更新复选框。）

Finally, here is an example of the directive in action on Plunker: http://plnkr.co/edit/3YNLsyoG4PIBW6Kj7dRK?p=preview 最后，这是一个关于Plunker的指令实例： http ：//plnkr.co/edit/3YNLsyoG4PIBW6Kj7dRK？p = preview

#5楼

There are two ways to approach this problem. 有两种方法可以解决这个问题。 Either use a simple array or an array of objects. 使用简单数组或对象数组。 Each solution has it pros and cons. 每种解决方案都有它的优点和缺点。 Below you'll find one for each case. 下面你会发现每个案例一个。

With a simple array as input data 用简单的数组作为输入数据

The HTML could look like: HTML可能如下所示：

<label ng-repeat="fruitName in fruits"><inputtype="checkbox"name="selectedFruits[]"value="{{fruitName}}"ng-checked="selection.indexOf(fruitName) > -1"ng-click="toggleSelection(fruitName)"> {{fruitName}}
</label>

And the appropriate controller code would be: 适当的控制器代码将是：

app.controller('SimpleArrayCtrl', ['$scope', function SimpleArrayCtrl($scope) {// Fruits$scope.fruits = ['apple', 'orange', 'pear', 'naartjie'];// Selected fruits$scope.selection = ['apple', 'pear'];// Toggle selection for a given fruit by name$scope.toggleSelection = function toggleSelection(fruitName) {var idx = $scope.selection.indexOf(fruitName);// Is currently selectedif (idx > -1) {$scope.selection.splice(idx, 1);}// Is newly selectedelse {$scope.selection.push(fruitName);}};
}]);

Pros : Simple data structure and toggling by name is easy to handle 优点：简单的数据结构和按名称切换很容易处理

Cons : Add/remove is cumbersome as two lists (the input and selection) have to be managed 缺点：添加/删除很麻烦，因为必须管理两个列表（输入和选择）

With an object array as input data 使用对象数组作为输入数据

The HTML could look like: HTML可能如下所示：

<label ng-repeat="fruit in fruits"><!--- Use `value="{{fruit.name}}"` to give the input a real value, in case the form gets submittedtraditionally- Use `ng-checked="fruit.selected"` to have the checkbox checked based on some angular expression(no two-way-data-binding)- Use `ng-model="fruit.selected"` to utilize two-way-data-binding. Note that `.selected`is arbitrary. The property name could be anything and will be created on the object if not present.--><inputtype="checkbox"name="selectedFruits[]"value="{{fruit.name}}"ng-model="fruit.selected"> {{fruit.name}}
</label>

And the appropriate controller code would be: 适当的控制器代码将是：

app.controller('ObjectArrayCtrl', ['$scope', 'filterFilter', function ObjectArrayCtrl($scope, filterFilter) {// Fruits$scope.fruits = [{ name: 'apple',    selected: true },{ name: 'orange',   selected: false },{ name: 'pear',     selected: true },{ name: 'naartjie', selected: false }];// Selected fruits$scope.selection = [];// Helper method to get selected fruits$scope.selectedFruits = function selectedFruits() {return filterFilter($scope.fruits, { selected: true });};// Watch fruits for changes$scope.$watch('fruits|filter:{selected:true}', function (nv) {$scope.selection = nv.map(function (fruit) {return fruit.name;});}, true);
}]);

Pros : Add/remove is very easy 优点：添加/删除非常简单

Cons : Somewhat more complex data structure and toggling by name is cumbersome or requires a helper method 缺点：更复杂的数据结构和按名称切换是麻烦的或需要帮助方法

Demo : http://jsbin.com/ImAqUC/1/ 演示： http ： //jsbin.com/ImAqUC/1/

#6楼

Since you accepted an answer in which a list was not used, I'll assume the answer to my comment question is "No, it doesn't have to be a list". 由于您接受了未使用列表的答案，我将假设我的评论问题的答案是“不，它不必是列表”。 I also had the impression that maybe you were rending the HTML server side, since "checked" is present in your sample HTML (this would not be needed if ng-model were used to model your checkboxes). 我也有这样的印象，也许你是在渲染HTML服务器端，因为样本HTML中存在“已检查”（如果使用ng-model对复选框进行建模，则不需要这样做）。

Anyway, here's what I had in mind when I asked the question, also assuming you were generating the HTML server-side: 无论如何，这是我在问这个问题时的想法，也假设您正在生成HTML服务器端：

<div ng-controller="MyCtrl" ng-init="checkboxes = {apple: true, orange: false, pear: true, naartjie: false}"><input type="checkbox" ng-model="checkboxes.apple">apple<input type="checkbox" ng-model="checkboxes.orange">orange<input type="checkbox" ng-model="checkboxes.pear">pear<input type="checkbox" ng-model="checkboxes.naartjie">naartjie<br>{{checkboxes}}
</div>

ng-init allows server-side generated HTML to initially set certain checkboxes. ng-init允许服务器端生成的HTML初始设置某些复选框。

Fiddle . 小提琴。