/*** 日志对象(构造函数)* @param id* @constructor*/
function MyLogger(id) {id = id || 'ADSLogWindow';//私有属性//日志窗口的DOM节点var logWindow = null;//私有方法//用受保护的方法创建日志窗口var createWindow = function () {//取得新窗口在浏览器中居中方知识的左上角位置var browserWindowSize = ADS.getBrowserWindowSize();var top = ((browserWindowSize.height - 200) / 2) || 0;var left = ((browserWindowSize.width - 200) / 2) || 0;//创建作为日志窗口的DOM节点//使用受保护的logWindow属性维护引用logWindow = document.createElement('ul');//指定ID值，以便必要时在DOM树中能够识别它logWindow.setAttribute('id', id);//在屏幕中居中定位日志窗口logWindow.style.position = 'absolute';logWindow.style.top = top + 'px';logWindow.style.left = left + 'px';//设置固定的大小并允许窗口内容滚动logWindow.style.width = '200px';logWindow.style.height = '200px';logWindow.style.overflow = 'scroll';//添加一些样式以美化外观logWindow.style.padding = '0';logWindow.style.margin = '0';logWindow.style.border = '1px solid black';logWindow.style.backgroundColor = 'white';logWindow.style.listStyle = 'none';logWindow.style.font = '10px/10px Verdana, Tahoma, Sans';//将其添加到文档主体中document.body.appendChild(logWindow);};//特权方法，（如果logWindow尚未定义，它还要调用受保护的createWindow()方法）/*** 向日志窗口中添加一条新纪录* @param {String} message* @return {Boolean}*/this.writeRaw = function (message) {//如果初始的窗口不存在，则创建它if (!logWindow) {createWindow();}//创建列表项并适当地添加样式var li = document.createElement('li');li.style.padding = '2px';li.style.border = '0';li.style.borderBottom = '1px dotted black';li.style.margin = '0';li.style.color = '#000';li.style.font = '12px/14px Verdana, Tahoma, Sans';//为日志节点添加信息if (typeof message === 'undefined') {li.appendChild(document.createTextNode('Message was undefined'));} else if (typeof li.innerHTML !== 'undefined') {//检查是否支持innerHTMLli.innerHTML = message;} else {li.appendChild(document.createTextNode(message));}//将这个条目添加到日志窗口logWindow.appendChild(li);return true;};
}
//公有方法
MyLogger.prototype = {/*** 对message中的尖括号进行编码以便在日志窗口中显示HTML源代码* @param {String} message*/write:function (message) {//警告message为空值时if (!message) {return this.writeRaw('ADS.log: null message');}//如果message不是字符串，则尝试调用toString()方法，//如果不存在该访问则记录对象类型if (typeof message !== 'string') {if (message.toString()) {return this.writeRaw(message);} else {return this.writeRaw(typeof message);}}//转换<和>以便innerHTML不会将message作为HTML进行解析message = message.replace(/</g, '<').replace(/>/g, '>');return this.writeRaw(message);},/*** 向日志窗口中添加加粗，红色的条目来充当标题* @param {String} message* @return {Boolean}*/header:function (message) {message = '<span style="color:white;background-color:black;font-weight:bold;padding:0 5px;">' + message + '</span>';return this.writeRaw(message);}
};if (!window.ADS) {window.ADS = {};
}window.ADS.log = new MyLogger();