详解AngularJS中自定义指令的使用

2019-11-20 12:13:41

字体：大中小

来源：转载

供稿：网友

自定义指令中使用AngularJS扩展HTML的功能。自定义指令使用的“指令”的功能定义。自定义指令只是替换了它被激活的元素。引导过程中AngularJS应用程序找到了匹配的元素，并做好使用自定义指令compile()方法一次活动再处理使用基于指令的范围自定义指令link()方法的元素。 AngularJS提供支持，以下列元素的类型来创建自定义指令。

Element directives - 指令遇到时激活一个匹配的元素。
Attribute - - 指令遇到时激活一个匹配的属性。
CSS - - 指令遇到时激活匹配CSS样式。
Comment - - 指令遇到时激活匹配的注释。

了解自定义指令

定义自定义的HTML标签。

<student name="Mahesh"></student><br/><student name="Piyush"></student>

定义自定义指令来处理上面的自定义HTML标签。

var mainApp = angular.module("mainApp", []);//Create a directive, first parameter is the html element to be attached.  //We are attaching student html tag. //This directive will be activated as soon as any student element is encountered in htmlmainApp.directive('student', function() {  //define the directive object  var directive = {};  //restrict = E, signifies that directive is Element directive  directive.restrict = 'E';  //template replaces the complete element with its text.   directive.template = "Student: <b>{{student.name}}</b> , Roll No: <b>{{student.rollno}}</b>";  //scope is used to distinguish each student element based on criteria.  directive.scope = {    student : "=name"  }  //compile is called during application initialization. AngularJS calls it once when html page is loaded.  directive.compile = function(element, attributes) {   element.css("border", "1px solid #cccccc");  //linkFunction is linked with each element with scope to get the element specific data.   var linkFunction = function($scope, element, attributes) {     element.html("Student: <b>"+$scope.student.name +"</b> , Roll No: <b>"+$scope.student.rollno+"</b><br/>");     element.css("background-color", "#ff00ff");   }   return linkFunction;  }  return directive;});

定义控制器以更新范围为指令。在这里，我们使用name属性值作为子的作用域。

mainApp.controller('StudentController', function($scope) {   $scope.Mahesh = {};   $scope.Mahesh.name = "Mahesh Parashar";   $scope.Mahesh.rollno = 1;   $scope.Piyush = {};   $scope.Piyush.name = "Piyush Parashar";   $scope.Piyush.rollno = 2;});

例子

<html><head>  <title>Angular JS Custom Directives</title></head><body>  <h2>AngularJS Sample Application</h2>  <div ng-app="mainApp" ng-controller="StudentController"> <student name="Mahesh"></student><br/> <student name="Piyush"></student>  </div>  <script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.2.15/angular.min.js"></script>  <script>   var mainApp = angular.module("mainApp", []);     mainApp.directive('student', function() {     var directive = {};     directive.restrict = 'E';     directive.template = "Student: <b>{{student.name}}</b> , Roll No: <b>{{student.rollno}}</b>";          directive.scope = {      student : "=name"     }       directive.compile = function(element, attributes) {      element.css("border", "1px solid #cccccc");      var linkFunction = function($scope, element, attributes) {        element.html("Student: <b>"+$scope.student.name +"</b> , Roll No: <b>"+$scope.student.rollno+"</b><br/>");        element.css("background-color", "#ff00ff");      }      return linkFunction;     }     return directive;   });     mainApp.controller('StudentController', function($scope) {      $scope.Mahesh = {};      $scope.Mahesh.name = "Mahesh Parashar";      $scope.Mahesh.rollno = 1;      $scope.Piyush = {};      $scope.Piyush.name = "Piyush Parashar";      $scope.Piyush.rollno = 2;   });     </script></body></html>

结果

在Web浏览器中打开textAngularJS.html。看到结果如下：

2015617113318563.jpg (560×240)