AngularJS expressions

AngularJS uses expressions to bind data to HTML.

AngularJS expression

AngularJS expression is written within double curly brackets: {{ expression }}.

AngularJS expressions bind data to HTML, which is similar to the ng-bind directive.

AngularJS will "output" the data where the expression is written.

AngularJS Expressions Much like JavaScript Expressions: They can contain literals, operators, and variables.

Instance{{ 5 + 5 }} or {{ firstName + " " + lastName }}

Instance

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script src="http://apps.bdimg.com/libs/angular.js/1.4.6/angular.min.js"></script> 
</head>
<body>

<div ng-app>
<p>我的第一个表达式: {{ 5 + 5 }}</p>
</div>

</body>
</html>

RunInstance»

Click the "Run Instance" button to view the online instance

AngularJS numbers

AngularJS numbers are just like JavaScript numbers:

Instance

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script src="http://apps.bdimg.com/libs/angular.js/1.4.6/angular.min.js"></script> 
</head>
<body>

<div ng-app="" ng-init="quantity=1;cost=5">
<p>总价: {{ quantity * cost }}</p>
</div>

</body>
</html>

Run instance»

Click the "Run instance" button to view the online instance

Use The same instance of ng-bind:

Instance

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script src="http://apps.bdimg.com/libs/angular.js/1.4.6/angular.min.js"></script> 
</head>
<body>

<div ng-app="" ng-init="quantity=1;cost=5">
<p>总价: <span ng-bind="quantity * cost"></span></p>
</div>

</body>
</html>

Run instance»

Click the "Run instance" button to view online Example

	Using ng-init is not very common. You'll learn a better way to initialize data in the Controllers chapter.

AngularJS Strings

AngularJS strings are just like JavaScript strings:

Example

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script src="http://apps.bdimg.com/libs/angular.js/1.4.6/angular.min.js"></script> 
</head>
<body>

<div ng-app="" ng-init="firstName='John';lastName='Doe'">

<p>姓名: {{ firstName + " " + lastName }}</p>

</div>

</body>
</html>

Run Instance»

Click the "Run Instance" button to view the online instance

The same instance using ng-bind:

Instance

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script src="http://apps.bdimg.com/libs/angular.js/1.4.6/angular.min.js"></script> 
</head>
<body>

<div ng-app="" ng-init="firstName='John';lastName='Doe'">

<p>姓名: <span ng-bind="firstName + ' ' + lastName"></span></p>

</div>

</body>
</html>

Run instance»

Click the "Run instance" button to view the online instance

AngularJS object

AngularJS Objects are like JavaScript objects:

Instance

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script src="http://apps.bdimg.com/libs/angular.js/1.4.6/angular.min.js"></script> 
</head>
<body>

<div ng-app="" ng-init="person={firstName:'John',lastName:'Doe'}">

<p>姓为 {{ person.lastName }}</p>

</div>

</body>
</html>

Run Instance»

Click the "Run Instance" button to view the online instance

The same instance using ng-bind:

Instance

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script src="http://apps.bdimg.com/libs/angular.js/1.4.6/angular.min.js"></script> 
</head>
<body>

<div ng-app="" ng-init="person={firstName:'John',lastName:'Doe'}">

<p>姓为 <span ng-bind="person.lastName"></span></p>

</div>

</body>
</html>

Running instance»

Click the "Run Instance" button to view the online example

AngularJS Array

AngularJS array is just like JavaScript array:

Example

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script src="http://apps.bdimg.com/libs/angular.js/1.4.6/angular.min.js"></script> 
</head>
<body>

<div ng-app="" ng-init="points=[1,15,19,2,40]">

<p>第三个值为 {{ points[2] }}</p>

</div>

</body>
</html>

Run Instance»

Click the "Run Instance" button to view the online instance

The same instance using ng-bind:

Instance

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script src="http://apps.bdimg.com/libs/angular.js/1.4.6/angular.min.js"></script> 
</head>
<body>

<div ng-app="" ng-init="points=[1,15,19,2,40]">

<p>第三个值为 <span ng-bind="points[2]"></span></p>

</div>

</body>
</html>

Run Instance»

Click the "Run Instance" button to view the online instance