最近使用到了ngOption实现下拉选择列表,由于需要实现分组等功能,百度了下没有太好的文章,就百度到一篇英文的帖子,按照其中的代码很顺利的搞定了。 本篇根据文中代码,详细讲述下如何实现下拉列表 更多内容参考:AngularJS知识总结
下拉列表的简单使用
ng-option指令使用很简单,只需要绑定两个属性:
一个是ng-model用于获取选定的值;
另一个是ng-options用于确定下拉列表的元素数组。
代码语言:javascript复制<select ng-model="engineer.currentActivity" class="form-control" ng-options="act for act in activities"></select>
上面这条语句就是把选择的值与engineer.currentActivity进行双向数据绑定,然后列表中的选项是activities中的每一个值。数据如下:
代码语言:javascript复制$scope.engineer = {
name: "Dani",
currentActivity: "Fixing bugs"
};
$scope.activities =
[
"Writing code",
"Testing code",
"Fixing bugs",
"Dancing"
];
运行结果如:
为了美观一点,这里引用了bootstrap。
代码语言:javascript复制<html ng-app="myApp">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<script src="http://apps.bdimg.com/libs/angular.js/1.2.16/angular.min.js"></script>
<link rel="stylesheet" href="http://apps.bdimg.com/libs/bootstrap/3.3.0/css/bootstrap.min.css">
<script src="http://apps.bdimg.com/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="http://apps.bdimg.com/libs/bootstrap/3.3.0/js/bootstrap.min.js"></script>
</head>
<body>
<div ng-controller="EngineeringController" class="container">
<div class="col-md-12">
{{engineer.name}} is currently: {{ engineer.currentActivity}}
</div>
<div class="col-md-4">
<label for="name">Choose a new activity:</label>
<select ng-model="engineer.currentActivity" class="form-control"
ng-options="act for act in activities">
</select>
</div>
</div>
<script type="text/javascript">
var myAppModule = angular.module("myApp",[]);
myAppModule.controller("EngineeringController",["$scope",function($scope){
$scope.engineer = {
name: "Dani",
currentActivity: "Fixing bugs"
};
$scope.activities =
[
"Writing code",
"Testing code",
"Fixing bugs",
"Dancing"
];
}]);
</script>
</body>
</html>
复杂对象,自定义列表名称
有的时候下拉列表并不是单纯的字符串数组,可能是json对象,例如:
代码语言:javascript复制$scope.activities =
[
{ id: 1, type: "Work" , name: "Writing code" },
{ id: 2, type: "Work" , name: "Testing code" },
{ id: 3, type: "Work" , name: "Fixing bugs" },
{ id: 4, type: "Play" , name: "Dancing" }
];
这个时候,绑定的数据就必须是与这里面的格式相同的数据,比如直接复制其中一条:
代码语言:javascript复制$scope.engineer = {
name: "Dani" ,
currentActivity: {
id: 3,
type: "Work" ,
name: "Fixing bugs"
}
};
当然也可以直接指定成:
代码语言:javascript复制$scope.engineer = {currentActivity:activities[3]}
然后在指令中可以循环列表拼接处下拉框的名称
代码语言:javascript复制<select
ng-model = "engineer.currentActivity"
class="form-control"
ng-options = "a.name ' (' a.type ')' for a in activities" >
</select >
运行效果如:
全部的代码如下:
代码语言:javascript复制<html ng-app="myApp">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<script src="http://apps.bdimg.com/libs/angular.js/1.2.16/angular.min.js"></script>
<link rel="stylesheet" href="http://apps.bdimg.com/libs/bootstrap/3.3.0/css/bootstrap.min.css">
<script src="http://apps.bdimg.com/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="http://apps.bdimg.com/libs/bootstrap/3.3.0/js/bootstrap.min.js"></script>
</head>
<body>
<div ng-controller="EngineeringController" class="container">
<div class="col-md-12">
{{engineer.name}} is currently: {{ engineer.currentActivity}}
</div>
<div class="col-md-4">
<label for="name">Choose a new activity:</label>
<select
ng-model = "engineer.currentActivity"
class="form-control"
ng-options = "a.name ' (' a.type ')' for a in activities" >
</select >
</div>
</div>
<script type="text/javascript">
var myAppModule = angular.module("myApp",[]);
myAppModule.controller("EngineeringController",["$scope",function($scope){
$scope.engineer = {
name: "Dani" ,
currentActivity: {
id: 3,
type: "Work" ,
name: "Fixing bugs"
}
};
$scope.activities =
[
{ id: 1, type: "Work" , name: "Writing code" },
{ id: 2, type: "Work" , name: "Testing code" },
{ id: 3, type: "Work" , name: "Fixing bugs" },
{ id: 4, type: "Play" , name: "Dancing" }
];
}]);
</script>
</body>
</html>
实现下拉列表的分组
其实分组与前面的例子很像,只要把空间中的ng-options的值换成下面:
代码语言:javascript复制<select ng-model = "engineer.currentActivity"
class="form-control"
ng-options = "a.name group by a.type for a in activities" >
</select >
添加 group by 就会按照后面的值进行分组
全部代码:
代码语言:javascript复制<html ng-app="myApp">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<script src="http://apps.bdimg.com/libs/angular.js/1.2.16/angular.min.js"></script>
<link rel="stylesheet" href="http://apps.bdimg.com/libs/bootstrap/3.3.0/css/bootstrap.min.css">
<script src="http://apps.bdimg.com/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="http://apps.bdimg.com/libs/bootstrap/3.3.0/js/bootstrap.min.js"></script>
</head>
<body>
<div ng-controller="EngineeringController" class="container">
<div class="col-md-12">
{{engineer.name}} is currently: {{ engineer.currentActivity}}
</div>
<div class="col-md-4">
<label for="name">Choose a new activity:</label>
<!-- <select
ng-model = "engineer.currentActivity"
class="form-control"
ng-options = "a.name ' (' a.type ')' for a in activities" >
</select > -->
<select ng-model = "engineer.currentActivity"
class="form-control"
ng-options = "a.name group by a.type for a in activities" >
</select >
</div>
</div>
<script type="text/javascript">
var myAppModule = angular.module("myApp",[]);
myAppModule.controller("EngineeringController",["$scope",function($scope){
$scope.engineer = {
name: "Dani" ,
currentActivity: {
id: 3,
type: "Work" ,
name: "Fixing bugs"
}
};
$scope.activities =
[
{ id: 1, type: "Work" , name: "Writing code" },
{ id: 2, type: "Work" , name: "Testing code" },
{ id: 3, type: "Work" , name: "Fixing bugs" },
{ id: 4, type: "Play" , name: "Dancing" }
];
}]);
</script>
</body>
</html>
按照id进行标识
由于之前的ng-model相当于初始的时候给设定了一个值。当你选择一个下拉列表选项的时候,就会覆盖掉这个初始值。
所以更多的时候会使用一个id进行标识,这样在初始化赋值的时候,只需要设定一个id就可以了。
代码语言:javascript复制$scope.engineer = {
currentActivityId: 3
};
$scope.activities =
[
{ id: 1, type: "Work" , name: "Writing code" },
{ id: 2, type: "Work" , name: "Testing code" },
{ id: 3, type: "Work" , name: "Fixing bugs" },
{ id: 4, type: "Play" , name: "Dancing" }
];
指令可以写成下面的格式
代码语言:javascript复制<select
ng-model = "engineer.currentActivityId"
class="form-control"
ng-options = "a.id as a.name group by a.type for a in activities" >
</select >
通过 as 前面的值,就可以确定唯一的一个选项
全部代码如下:
代码语言:javascript复制<html ng-app="myApp">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<script src="http://apps.bdimg.com/libs/angular.js/1.2.16/angular.min.js"></script>
<link rel="stylesheet" href="http://apps.bdimg.com/libs/bootstrap/3.3.0/css/bootstrap.min.css">
<script src="http://apps.bdimg.com/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="http://apps.bdimg.com/libs/bootstrap/3.3.0/js/bootstrap.min.js"></script>
</head>
<body>
<div ng-controller="EngineeringController" class="container">
<div class="col-md-12">
current is: {{ engineer.currentActivityId}}
</div>
<div class="col-md-4">
<label for="name">Choose a new activity:</label>
<select
ng-model = "engineer.currentActivityId"
class="form-control"
ng-options = "a.id as a.name group by a.type for a in activities" >
</select >
</div>
</div>
<script type="text/javascript">
var myAppModule = angular.module("myApp",[]);
myAppModule.controller("EngineeringController",["$scope",function($scope){
$scope.engineer = {
currentActivityId: 3
};
$scope.activities =
[
{ id: 1, type: "Work" , name: "Writing code" },
{ id: 2, type: "Work" , name: "Testing code" },
{ id: 3, type: "Work" , name: "Fixing bugs" },
{ id: 4, type: "Play" , name: "Dancing" }
];
}]);
</script>
</body>
</html>
参考
Using ngOptions in AngularJS:http://odetocode.com/blogs/scott/archive/2013/06/19/using-ngoptions-in-angularjs.aspx