//define a module
var mainApp = angular.module("mainApp", []);
//create a value object as "defaultInput" and pass it a data.
mainApp.value("defaultInput", 5);
...
//inject the value in the controller using its name "defaultInput"
mainApp.controller('CalcController', function($scope, CalcService, defaultInput) {
   $scope.number = defaultInput;
   $scope.result = CalcService.square($scope.number);

   $scope.square = function() {
   $scope.result = CalcService.square($scope.number);
  }
});

工廠

工廠是用于返回函數(shù)的值。它根據(jù)需求創(chuàng)造值，每當(dāng)一個(gè)服務(wù)或控制器需要。它通常使用一個(gè)工廠函數(shù)來(lái)計(jì)算并返回對(duì)應(yīng)值

//define a module
var mainApp = angular.module("mainApp", []);
//create a factory "MathService" which provides a method multiply to return multiplication of two numbers
mainApp.factory('MathService', function() {   
  var factory = {}; 
  factory.multiply = function(a, b) {
   return a * b 
  }
  return factory;
}); 

//inject the factory "MathService" in a service to utilize the multiply method of factory.
mainApp.service('CalcService', function(MathService){
   this.square = function(a) { 
   return MathService.multiply(a,a); 
  }
});
...

服務(wù)

服務(wù)是一個(gè)單一的JavaScript包含了一組函數(shù)對(duì)象來(lái)執(zhí)行某些任務(wù)。服務(wù)使用service()函數(shù)，然后注入到控制器的定義。

//define a module
var mainApp = angular.module("mainApp", []);
...
//create a service which defines a method square to return square of a number.
mainApp.service('CalcService', function(MathService){
   this.square = function(a) { 
   return MathService.multiply(a,a); 
  }
});
//inject the service "CalcService" into the controller
mainApp.controller('CalcController', function($scope, CalcService, defaultInput) {
   $scope.number = defaultInput;
   $scope.result = CalcService.square($scope.number);

   $scope.square = function() {
   $scope.result = CalcService.square($scope.number);
  }
});

提供者

提供者所使用的AngularJS內(nèi)部創(chuàng)建過(guò)程中配置階段的服務(wù)，工廠等(相AngularJS引導(dǎo)自身期間)。下面提到的腳本，可以用來(lái)創(chuàng)建，我們已經(jīng)在前面創(chuàng)建MathService。提供者是一個(gè)特殊的工廠方法以及get()方法，用來(lái)返回值/服務(wù)/工廠。

//define a module
var mainApp = angular.module("mainApp", []);
...
//create a service using provider which defines a method square to return square of a number.
mainApp.config(function($provide) {
  $provide.provider('MathService', function() {
   this.$get = function() {
     var factory = {}; 
     factory.multiply = function(a, b) {
      return a * b; 
     }
     return factory;
   };
  });
});

常量

常量用于通過(guò)配置相位值考慮事實(shí)，值不能使用期間的配置階段被傳遞。

mainApp.constant("configParam", "constant value");

例子

下面的例子將展示上述所有指令。

testAngularJS.html

<html>
<head>
  <title>AngularJS Dependency Injection</title>
</head>
<body>
  <h2>AngularJS Sample Application</h2>
  <div ng-app="mainApp" ng-controller="CalcController">
   <p>Enter a number: <input type="number" ng-model="number" />
   <button ng-click="square()">X<sup>2</sup></button>
   <p>Result: {{result}}</p>
  </div>
  <script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.2.15/angular.min.js"></script>
  <script>
   var mainApp = angular.module("mainApp", []);
	 
   mainApp.config(function($provide) {
     $provide.provider('MathService', function() {
      this.$get = function() {
        var factory = {}; 
        factory.multiply = function(a, b) {
         return a * b; 
        }
        return factory;
      };
     });
   });

   mainApp.value("defaultInput", 5);

   mainApp.factory('MathService', function() {   
     var factory = {}; 
     factory.multiply = function(a, b) {
      return a * b; 
     }
     return factory;
   }); 

   mainApp.service('CalcService', function(MathService){
      this.square = function(a) { 
      return MathService.multiply(a,a); 
     }
   });

   mainApp.controller('CalcController', function($scope, CalcService, defaultInput) {
      $scope.number = defaultInput;
      $scope.result = CalcService.square($scope.number);

      $scope.square = function() {
      $scope.result = CalcService.square($scope.number);
     }
   });
  </script>
</body>
</html>

結(jié)果

在Web瀏覽器打開(kāi)textAngularJS.html?？吹浇Y(jié)果如下。