Implementing command mode with JavaScript

Command|javascript

The realization is simply too simple ... A dynamic language is a good thing.
First define a command object with the following code:

function Command (obj) {
var commandobj = obj; Save the reference of working object
var oldprop = new Object (); Save Old properties

Set new properties and save old properties
This. do = function () {
for (Var o in this) {
Oldprop[o] = Commandobj[o];
Commandobj[o] = This[o];
}
}

Restore Old Properties
This. Undo = function () {
for (Var o in Oldprop) {
Commandobj[o] = Oldprop[o];
}

Delete Oldprop;
Oldprop = new Object ();
}
}

If you want to invoke it, you can write it:

"MC" is a object that has _alpha and _x attributes

var com = new Command (MC);
Com._alpha = 20;
com._x = 200;
Com. Do ();
Do something ...
Remember to save this Command somewhere ...

Now, undo it!
Com. Undo ();

Marvel at the simplicity and harmony of this!