<html> <head> <title>Example</title> <script type="text/javascript"> /*------------------------------------------------------------------------------ * JavaScript zInherit Library * Version 1.0 * by Nicholas C. Zakas, http://www.nczonline.net/ * Copyright (c) 2004-2005 Nicholas C. Zakas. All Rights Reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation; either version 2.1 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA *------------------------------------------------------------------------------ */
/** * Inherits properties and methods from the given class. * @scope public * @param fnClass The constructor function to inherit from. */ Object.prototype.inheritFrom = function (fnClass /*: Function */) /*:void*/ {
/** * Inherits all classes going up the inheritance chain recursively. * @param fnClass The class to inherit from. * @param arrClasses The array of classes to build up. * @scope private */ function inheritClasses(fnClass /*:Function*/, arrClasses /*:Array*/) /*:void*/ {
arrClasses.push(fnClass);
if (typeof fnClass.__superclasses__ == "object") { for (var i=0; i < fnClass.__superclasses__.length; i++){ inheritClasses(fnClass.__superclasses__[i], arrClasses); } } }
if (typeof this.constructor.__superclasses__ == "undefined") { this.constructor.__superclasses__ = new Array(); }
for (prop in fnClass.prototype) { if (typeof fnClass.prototype[prop] == "function") { this[prop] = fnClass.prototype[prop]; } } };
/** * Determines if the given object is an instance of a given class. * This method is necessary because using {@link #inheritFrom} renders * the JavaScript <code>instanceof</code> operator useless. * @param fnClass The constructor function to test. * @return True if the object is an instance of the class, false if not. * @scope public */ Object.prototype.instanceOf = function (fnClass /*:Function*/) /*: boolean */ {
if (this.constructor == fnClass) { return true; } else if (typeof this.constructor.__superclasses__ == "object") { for (var i=0; i < this.constructor.__superclasses__.length; i++) { if (this.constructor.__superclasses__[i] == fnClass) { return true; } } return false; } else { return false; } };
</script> </head> <body> <script type="text/javascript"> function ClassX() { this.messageX = "This is the X message.";
if (typeof ClassX._initialized == "undefined") {
ClassX.prototype.sayMessageX = function () { alert(this.messageX); };
ClassX._initialized = true; } }
function ClassY() { this.messageY = "This is the Y message.";
if (typeof ClassY._initialized == "undefined") {
ClassY.prototype.sayMessageY = function () { alert(this.messageY); };
ClassY._initialized = true; } }
function ClassZ() { ClassX.apply(this); ClassY.apply(this); this.messageZ = "This is the Z message.";
