我想知道这种在javascript中编写可重用代码的方法

Question

I was looking into a tutorial sometime ago and in that tutorial the author was using following approach to write reusable code. I am trying to find that tutorial but no avail yet. I would like to know a little about following approach and how can I reuse this with new operator without adding the module to global namespace?

(function(factory) {

})(function() {
    // All of the logic code was here in that tutorial.
});

Answer 1

I think you should check out the module pattern which is aimed at creating reusable well encapsulated javascript components

here is a short example

 MyModule = function(){
      var privateAttribute = 2;
      return {
         publicAttribute : "this is a public attribute";
         publichMethod : function (param1){console.log(param1);}
      }

 }();

var module = MyModule;
module.putlicMethod("hello world");

Answer 2

So, the idea is that the second function is what you are passing in as the factory parameter in the first function, so you would create instances of factory and write code against those instances in the TOP function - not the bottom function. The bottom function is your module definition.

Thanks to @Bergi for getting me started on the right track.

Here's an example with code:

 (function(factory) { var constructor = new factory(); var obj1 = new constructor(); var obj2 = new constructor(); console.log("obj1: ", obj1); console.log("obj2: ", obj2); })(function() { return function() { return { prop1: "123", prop2: "ABC" } } }); 

Answer 3

From your code example it is difficult to know exactly what you are looking for, but the code looks similar to the Universal Module Definition pattern (UMD) used to define reusable modules for use with various module loaders.

An example of UMD ( taken from this page ) which illustrates what you describe in your code—the actual code logic (the module) in the lower function, which is passed as the argument factory to the upper function which handles the module setup:

(function (root, factory) {
    if (typeof define === 'function' && define.amd) {
        // AMD
        define(['jquery'], factory);
    } else if (typeof exports === 'object') {
        // Node, CommonJS-like
        module.exports = factory(require('jquery'));
    } else {
        // Browser globals (root is window)
        root.returnExports = factory(root.jQuery);
    }
}(this, function ($) {
    //    methods
    function myFunc(){};

    //    exposed public method
    return myFunc;
}));