jQuery.holdReady()
暂停或恢复.ready() 事件的执行。
分类：Document Loading
jQuery.ready
A Promise-like object (or "thenable") that resolves when the document is ready.
load event
为 JavaScript 的 "load" 事件绑定一个处理函数。
.load()
Bind an event handler to the "load" event, or trigger that event on an element.
.ready()
当DOM准备就绪时，指定一个函数来执行。
.unload()
Bind an event handler to the "unload" event, or trigger that event on an element.
unload event
为 JavaScript 的 "unload" 事件绑定一个处理函数。