ng-option
select
是 AngularJS 预设的一组directive。下面是其官网api doc给出的用法:AngularJS:select
大意是,select
中的ngOption
可以采用和ngRepeat
指令类似的循环结构,其data source可以是array或者是object。针对两种data source又有衍生的好几种用法。但是官网的例子实在是太少了。
下面是针对几个不太容易理解的用法的例子。
先上controller
<!-- lang: js -->
function selectCtrl($scope) {
$scope.selected = '';
$scope.model = [{
id: 10001,
mainCategory: '男',
productName: '水洗T恤',
productColor: '白'
}, {
id: 10002,
mainCategory: '女',
productName: '圆领短袖',
productColor: '黑'
}, {
id: 10003,
mainCategory: '女',
productName: '短袖短袖',
productColor: '黃'
}];
}
实例一:基本下拉效果
usage: label for value in array
<select ng-model="selected" ng-options="m.productName for m in model">
<option value="">-- 请选择 --</option></select>
效果:
说明
- usage中的 value 也就是 ng-options 中的 m,而 m 是数组model的一个元素,它是一个变量
- usage中的 label 也就是 ng-options 中的
m.productName
, 其实就是一个 AngularJS Expression
实例二:自定义下拉显示名称
usage: label for value in array
<select ng-model="selected" ng-options="(m.productColor + ' - ' + m.productName) for m in model">
<option value="">-- 请选择 --</option></select>
效果
说明
- 可以看到,usage 中的 label 可以根据需求拼接出不同的字符串
实例三: 让选项分组
usage: label group by group for value in array
<select ng-model="selected" ng-options="(m.productColor + ' - ' + m.productName) group by m.mainCategory for m in model">
<option value="">-- 请选择 --</option></select>
效果
说明
- 这里使用了
group by
,通过$scope.model
中的mainCategory
字段进行分组
实例四:自定义ngModel
的值
usage: select as label for value in array
<select ng-model="selected" ng-options="m.id as m.productName for m in model">
<option value="">-- 请选择 --</option></select>
效果
说明
- 这种用法也是select指令最复杂的一种。从效果中可以看出,usage中select的作用就是重新定义
ng-model
的值。在这里,ng-model等于m.id,当ng-model
发生改变的时候,得到的是m.id
的值
参考
- http://docs.angularjs.org/api/ng.directive:select
- http://blog.miniasp.com/post/2013/05/12/AngularJS-ng-module-select-ngOptions-usage-samples.aspx
一、用法
ngOption针对不同类型的数据源有不同的用法,主要体现在数组和对象上。
数组:
label for value in array
select as label for value in array
label group by group for value in array
select as label group by group for value in array
select as label group by group for value in array track by trackexpr
对象:
label for ( key , value ) in object
select as label for ( key , value ) in object
label group by group for ( key , value ) in object
select as label group by group for ( key , value ) in object
说明:
array / object: 数据源的类型,有数组和对象两种
value:迭代过程中,引用数组的项或者对象的属性值
key:迭代过程中,引用对象的属性名
label:选项显示的标签,用户可看到的
select:结果绑定到ngModel中,如果没有指定,则默认绑定value
group:group by的条件,表示按某条件进行分组
trackexpr:用于唯一确定数组中的迭代项的表达式
二、实例
通用的js代码:
<script> var MyModule = angular.module("MyModule",[]); MyModule.controller("Ctrl",["$scope", function($scope){ $scope.colors = [ {name:'black', shade:'dark'}, {name:'white', shade:'light'}, {name:'red', shade:'dark'}, {name:'blue', shade:'dark'}, {name:'yellow', shade:'light'} ]; $scope.object = { dark: "black", light: "red", lai: "red" }; }]); </script>
label for value in array
html:
<select ng-model="myColor" ng-options="color.name for color in colors"></select>
效果:
select as label for value in array
html:
<select ng-model="myColor" ng-options="color.shade as color.name for color in colors"></select>
效果:
label group by group for value in array
html:
<select ng-model="myColor" ng-options="color.name group by color.shade for color in colors"></select>
效果:
select as label group by group for value in array
html:
<select ng-model="myColor" ng-options="color.name as color.name group by color.shade for color in colors">
效果:
select as label group by group for value in array track by trackexpr
html:
<select ng-model="myColor" ng-options="color.name for color in colors track by color.name">
效果:
label for ( key , value ) in object
html:
<select ng-model="obj" ng-options="key for (key, value) in object"></select>
效果:
select as label for ( key , value ) in object
html:
<select ng-model="obj" ng-options="key as key for (key, value) in object"></select>
效果:
label group by group for ( key , value ) in object
html:
<select ng-model="obj" ng-options="key group by value for (key, value) in object"></select>
效果:
select as label group by group for ( key , value ) in object
html:
<select ng-model="obj" ng-options="key as key group by value for (key, value) in object"></select>
效果: