AngularJS语法详解

  模板和数据的基本运作流程如下:

  用户请求应用起始页面

  用户的浏览器向服务器发起一次http连接,然后加载index.html页面,这个页面包含了模板

  angular被加载到页面中,等待页面加载完成,查找ng-app指令,用来定义模板的边界

  angular遍历模板,查找指定和绑定关系,将触发一些列动作:注册监听器、执行一些DOM操作、从服务器获取初始化数据。最后,应用将会启动起来,并将模板转换成DOM视图

  连接到服务器去加载需要展示给用户的其他数据

  显示文本

  

  一种使用{{}}形式,如{{greeting}} 第二种ng-bind="greeting"

  使用第一种,未被渲染的页面可能会被用户看到,index页面建议使用第二种,其余的页面可以使用第一种

  表单输入

  

复制代码 代码如下:

  <html ng-app>

  <head>

  <title>表单</title>

  <script type="text/javascript" src="angular.min.js"></script>

  <script type="text/javascript">

  function StartUpController($scope) {

  $scope.funding = {startingEstimate:0};

  computeNeeded = function() {

  $scope.funding.needed = $scope.funding.startingEstimate * 10;

  };

  $scope.$watch('funding.startingEstimate',computeNeeded); //watch model的变化

  }

  </script>

  </head>

  <body>

  <form ng-controller="StartUpController">

  Starting: <input ng-change="computeNeeded()" ng-model="funding.startingEstimate">  //change的时候调用函数

  Recommendation: {{funding.needed}}

  </form>

  </body>

  </html>

  在某些情况下,我们不想一有变化就立刻做出动作,而是要进行等待。例如:

  

复制代码 代码如下:

  <html ng-app>

  <head>

  <title>表单</title>

  <script type="text/javascript" src="angular.min.js"></script>

  <script type="text/javascript">

  function StartUpController($scope) {

  $scope.funding = {startingEstimate:0};

  computeNeeded = function() {

  $scope.funding.needed = $scope.funding.startingEstimate * 10;

  };

  $scope.$watch('funding.startingEstimate',computeNeeded);//watch监视一个表达式,当这个表达式发生变化时就会调用一个回调函数

  $scope.requestFunding = function() {

  window.alert("Sorry,please get more customers first.")

  };

  }

  </script>

  </head>

  <body>

  <form ng-submit="requestFunding()" ng-controller="StartUpController">  //ng-submit

  Starting: <input ng-change="computeNeeded()" ng-model="funding.startingEstimate">

  Recommendation: {{funding.needed}}

  <button>Fund my startup!</button>

  </form>

  </body>

  </html>

  非表单提交型的交互,以click为例

  

复制代码 代码如下:

  <html ng-app>

  <head>

  <title>表单</title>

  <script type="text/javascript" src="angular.min.js"></script>

  <script type="text/javascript">

  function StartUpController($scope) {

  $scope.funding = {startingEstimate:0};

  computeNeeded = function() {

  $scope.funding.needed = $scope.funding.startingEstimate * 10;

  };

  $scope.$watch('funding.startingEstimate',computeNeeded);

  $scope.requestFunding = function() {

  window.alert("Sorry,please get more customers first.")

  };

  $scope.reset = function() {

  $scope.funding.startingEstimate = 0;

  };

  }

  </script>

  </head>

  <body>

  <form ng-controller="StartUpController">

  Starting: <input ng-change="computeNeeded()" ng-model="funding.startingEstimate">

  Recommendation: {{funding.needed}}

  <button ng-click="requestFunding()">Fund my startup!</button>

  <button ng-click="reset()">Reset</button>

  </form>

  </body>

  </html>

  列表、表格以及其他迭代型元素

  ng-repeat会通过$index返回当前引用的元素序号。 示例代码如下:

  

复制代码 代码如下:

  <html ng-app>

  <head>

  <title>表单</title>

  <script type="text/javascript" src="angular.min.js"></script>

  <script type="text/javascript">

  var students = [{name:'Mary',score:10},{name:'Jerry',score:20},{name:'Jack',score:30}]

  function StudentListController($scope) {

  $scope.students = students;

  }

  </script>

  </head>

  <body>

  <table ng-controller="StudentListController">

  <tr ng-repeat='student in students'>

  <td>{{$index+1}}</td>

  <td>{{student.name}}</td>

  <td>{{student.score}}</td>

  </tr>

  </table>

  </body>

  </html>

  隐藏与显示

  ng-show和ng-hide功能是等价的,但是运行效果正好相反。

  

复制代码 代码如下:

  <html ng-app>

  <head>

  <script type="text/javascript" src="angular.min.js"></script>

  <script>

  function DeathrayMenuController($scope) {

  $scope.menuState = {show:false };//这里换成menuState.show = false 效果就显示不出来了。以后声明变量还是放在{}里面吧

  $scope.toggleMenu = function() {

  $scope.menuState.show = !$scope.menuState.show;

  };

  }

  </script>

  </head>

  <body>

  <div ng-controller='DeathrayMenuController'>

  <button ng-click='toggleMenu()'>Toggle Menu</button>

  <ul ng-show='menuState.show'>

  <li ng-click='stun()'>Stun</li>

  <li ng-click='disintegrate()'>Disintegrate</li>

  <li ng-click='erase()'>Erase from history</li>

  </ul>

  </div>

  </body>

  </html>

  css类和样式

  ng-class和ng-style都可以接受一个表达式,表达式执行的结果可能是如下取值之一:

  表示css类名的字符串,以空格分隔

  css类名数组

  css类名到布尔值的映射

  代码示例如下:

  

复制代码 代码如下:

  <html ng-app>

  <head>

  <style type="text/css">

  .error {

  background-color: red;

  }

  .warning {

  background-color: yellow;

  }

  </style>

  <script type="text/javascript" src="angular.min.js"></script>

  <script>

  function HeaderController($scope) {

  $scope.isError = false;

  $scope.isWarning = false;

  $scope.showError = function() {

  $scope.messageText = "Error!!!!"

  $scope.isError = true;

  $scope.isWarning = false;

  }

  $scope.showWarning = function() {

  $scope.messageText = "Warning!!!"

  $scope.isWarning = true;

  $scope.isError = true;

  }

  }

  </script>

  </head>

  <body>

  <div ng-controller="HeaderController">

  <div ng-class="{error:isError,warning:isWarning}">{{messageText}}</div>

  <button ng-click="showError()">Error</button>

  <button ng-click="showWarning()">Warning</button>

  </div>

  </body>

  </html>

  css类名到布尔值的映射

  示例代码如下:

  

复制代码 代码如下:

  <html ng-app>

  <head>

  <style type="text/css">

  .selected {

  background-color: lightgreen;

  }

  </style>

  <script type="text/javascript" src="angular.min.js"></script>

  <script>

  function Restaurant($scope) {

  $scope.list = [{name:"The Handsome",cuisine:"BBQ"},{name:"Green",cuisine:"Salads"},{name:"House",cuisine:'Seafood'}];

  $scope.selectRestaurant = function(row) {

  $scope.selectedRow = row;

  }

  }

  </script>

  </head>

  <body>

  <table ng-controller="Restaurant">

  <tr ng-repeat='restaurant in list' ng-click='selectRestaurant($index)' ng-class='{selected: $index==selectedRow}'>  //css类名到布尔值的映射,当模型属性selectedRow的值等于ng-repeat中得$index时,selectd样式就会被设置到那一行

  <td>{{restaurant.name}}</td>

  <td>{{restaurant.cuisine}}</td>

  </tr>

  </table>

  </body>

  </html>