function $(str)
{
	return document.getElementById(str);
}

function isIE()
{
	if (document.readyState)
	{
		return true;
	}
	else
	{
		return false;
	}
}

//延迟加载 -- 当页面load完成时候加载 
function wait(Command)
{
	if (isIE())
	{
		if (document.readyState == "complete")
		{
			eval(Command);
		}
		else
		{
			setTimeout("wait(\"" + Command + "\")",50);
		}
	}
	else
	{
		window.addEventListener("DOMContentLoaded",	function(){ setTimeout("wait(\"" + Command + "\")",50); },false);
	}
}