Dưới đây là ví dụ với ý kiến chi tiết:
(function(){
/* function constructor */
function Sandbox(){
//Change arguments to array, as you know 'arguments' are not a true JS array
//Array.prototype.slice will provide shallow copy of 'arguments'
var args = Array.prototype.slice.call(arguments),
//remove last element from array and return it to caller
//our last argument is callback
callback = args.pop(),
//We can pass modules as strings or as array
//if first element is a string, take all arguemnts
//otherwise take one element (array)
modules = (args[0] && typeof args[0] === "string") ? args : args[0],
modulesLength = modules.length,
i;
//handle calling function constructor without 'new' keyword
if(!(this instanceof Sandbox)){
//Invoke me again!
return new Sandbox(modules, callback);
}
//we can add properties to 'this'
this.someProp = "Initialized property";
//Initialize all required modules
for(i = 0; i < modulesLength ; i++){
//pass reference to 'this' for each required module and invoke it
//'this' is poiting to new object which was created
//after calling new Sandbox()
Sandbox.modules[modules[i]](this);
}
//Invoke callback and pass 'this'
//now 'this' cotains all methods and properties
//attached in modules functions
callback(this);
};
//We can optionally create Sandbox methods
Sandbox.prototype = {
version: "1.0.1",
createdAt: new Date()
};
/* function as a first class object - saving all modules*/
Sandbox.modules = {};
/*Create $http,$scope and $ajax modules */
/*We need box object to add new functionality*/
/*We are creating new methods by attatching them to box obect*/
/*box is a reference to 'this' called as initializator from function constructor*/
Sandbox.modules.$http = function(box){
box.get = function(){
console.log("$http.get");
};
box.post = function(){
console.log("$http.post");
};
box.prop = "I'm $http property";
};
Sandbox.modules.$scope = function(box){
box.inject = function(param1, param2){
console.log("$scope.inject: " + param1 + " " + param2);
};
box.destroy = function(o){
console.log("$scope.destroy: " + o + " has been destroyed!");
};
};
Sandbox.modules.$ajax = function(box){
box.call = function(){
console.log("$ajax.call");
};
};
//Sandbox without calling 'new' was handled in function constructor
//We are requesting for 2 modules: $scope and $http
//callback function is our new playground
//box object has $scope and $http methods and properties inside, we are ready to go!
Sandbox(["$scope", '$http'], function(box){
console.log(box); //contains methods from $scope and $http
console.log(box.inject("John", "Doe"));
console.log(box.post());
//we can event nest our playgrounds
Sandbox(["$ajax"], function(box){
console.log(box); //contains only $ajax methods and properties
console.log(box.call());
//we can't invoke $scope or $http functions here
});
//we can't invoke $ajax functions here
});
})();
Liên kết đến JSFiddle: http://jsfiddle.net/Lodse4hj/
Nguồn
2015-07-28 18:59:23
Có một cái nhìn tại [requirejs] (http://requirejs.org/). Hàm 'require' hoạt động khá giống với mẫu sandbox, chỉ với tính năng bổ sung của tải module lười biếng. – Bergi