无法从 $injector.get() 获取服务实例

我定义了一个名为“greeting”的客户服务，但无法从 $injector.get('greeting') 获取该实例。它会抛出这样的错误：未知提供者：greetingProvider 。那么哪种方式才是正确的获取方式呢？以下是代码：

var app = angular.module('myDI', []);
app.config(function($provide){
    $provide.provider('greeting', function(){
        this.$get = function(){
             return function(name) {
                 console.log("Hello, " + name);
            };
        };
    });
});

var injector = angular.injector();
var greeting = injector.get('greeting');
greeting('Ford Prefect');

您需要从模块创建注入器。

var app = angular.module('myDI', []);
app.config(function($provide){
    $provide.provider('greeting', function(){
        this.$get = function(){
             return function(name) {
                 console.log("Hello, " + name);
            };
        };
    });
});
var injector = angular.injector(['myDI', 'ng']); //Add this line
var greeting = injector.get('greeting');
greeting('Ford Prefect');
var injector = angular.injector();

在这里尝试一下。FIDDLE http://jsfiddle.net/vVV8H/1/