// JScript 文件
function $get(objectId)
{
    if(document.getElementById && document.getElementById(objectId))// W3C DOM
    {
		return document.getElementById(objectId);
	}
	else if (document.all && document.all(objectId)) // MSIE 4 DOM
	{
		return document.all(objectId);
	}
	else if (document.layers && document.layers[objectId]) // NN 4 DOM.. note: this won't find nested layers
	{
		return document.layers[objectId];
	}
	else
	{
		return false;
	}
}