Home > Article > Web Front-end > AngularJS uses ngOption to implement drop-down list example code_AngularJS

AngularJS uses ngOption to implement drop-down list example code_AngularJS

WBOYOriginal: 2016-05-16 15:18:351384browse

Simple use of drop-down lists

The

ng-option directive is very simple to use. You only need to bind two attributes:

One is ng-model used to get the selected value;

The other is the array of elements used by ng-options to determine the drop-down list.

<select ng-model="engineer.currentActivity" class="form-control" ng-options="act for act in activities"></select>

The above statement is to perform two-way data binding between the selected value and engineer.currentActivity, and then the options in the list are each value in activities. The data is as follows:

$scope.engineer = {
name: "Dani",
currentActivity: "Fixing bugs"
};
$scope.activities =
[
"Writing code",
"Testing code",
"Fixing bugs",
"Dancing"
];

The operation results are as follows:

For the sake of beauty, bootstrap is quoted here.

<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>

Complex object, custom list name

Sometimes the drop-down list is not a simple string array, but may be a json object, for example:

$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" }
];

At this time, the bound data must be in the same format as the data here, for example, directly copy one of them:

$scope.engineer = {
name: "Dani" ,
currentActivity: {
id: 3,
type: "Work" ,
name: "Fixing bugs"
}
};

Of course, you can also specify it directly as:

$scope.engineer = {currentActivity:activities[3]}

Then in the command you can loop through the names of the drop-down boxes where the list is spliced

<select 
ng-model = "engineer.currentActivity"
class="form-control"
ng-options = "a.name +' (' + a.type + ')' for a in activities" > 
</select >

The operation effect is as follows:

All the codes are as follows:





 






{{engineer.name}} is currently: {{ engineer.currentActivity}}


Choose a new activity: 
<select 
ng-model = "engineer.currentActivity"
class="form-control"
ng-options = "a.name +' (' + a.type + ')' for a in activities" > 
</select >

Implementing grouping of drop-down lists

In fact, grouping is very similar to the previous example. Just change the value of ng-options in the space to the following:

<select ng-model = "engineer.currentActivity"
class="form-control"
ng-options = "a.name group by a.type for a in activities" > 
</select >

Add group by and it will be grouped according to the following value

All codes:





 






{{engineer.name}} is currently: {{ engineer.currentActivity}}


Choose a new activity: 

<select ng-model = "engineer.currentActivity"
class="form-control"
ng-options = "a.name group by a.type for a in activities" > 
</select >

Identify by id

Because the previous ng-model is equivalent to setting a value initially. This initial value is overwritten when you select a drop-down list option.

So more often an id will be used for identification, so that when initializing the assignment, you only need to set an id.

$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" }
];

The command can be written in the following format

<select 
ng-model = "engineer.currentActivityId"
class="form-control"
ng-options = "a.id as a.name group by a.type for a in activities" > 
</select >

By the value in front of as, you can determine the only option

All codes are as follows:





 






current is: {{ engineer.currentActivityId}}


Choose a new activity: 
<select 
ng-model = "engineer.currentActivityId"
class="form-control"
ng-options = "a.id as a.name group by a.type for a in activities" > 
</select >

The above is the example code that the editor shared with you for using ngOption to implement a drop-down list in AngularJS. I hope it will be helpful to you.

Statement：

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Previous article：How to implement SMS verification code based on JavaScript_javascript skillsNext article：How to implement SMS verification code based on JavaScript_javascript skills

See more

AngularJS uses ngOption to implement drop-down list example code_AngularJS

Related articles