关于readyState

DOM readyState

• uninitialized 还未开始载入
• loading 载入中
• interactive 已加载
• complete 载入完成

ajax readyState

• 0 (Uninitialized): The object has been created but the open() method hasn’t been called.
• 1 (Loading): The open() method has been called but the request hasn’t been sent.
• 2 (Loaded): The request has been sent.
• 3 (Interactive). A partial response has been received.
• 4 (Complete): All data has been received and the connection has been closed.

function log() {    try{        console.log.apply(console, arguments);    }catch(e) {        try{            opera.postError.apply(opera, arguments);        }catch(e) {            alert([].join.call(arguments, ''))        }    }}