//供求信息定时切换
var pds = null;
var cid = 0;
var cimg = null;
var autoid = 1;
var pdtt = null;
function pdin(img, pdid)
{
	if (pdtt)
	{
		window.clearInterval(pdtt);
		pdtt = null;
	}
	chg_pd_(img, pdid);
}

function chg_pd_(img, pdid)
{
	if (pdid == cid)
	{
		return;
	}
	if (!pds)
	{
		pds = document.getElementById("prvdinfo").getElementsByTagName("div");
	}
	if (pdid < pds.length)
	{
		if (!cimg)
		{
			cimg = document.getElementById("imgpd0");
		}
//		cimg.src = cimg.src.replace("a.GIF", "b.GIF");
		cimg.className = "pdnormal";
		pds[cid].style.display = "none";
//		img.src = img.src.replace("b.GIF", "a.GIF");
		img.className = "pdfocus";
		pds[pdid].style.display = "block";
		cid = pdid;
		cimg = img;
	}
}

function chg_pd()
{
	chg_pd_(document.getElementById("imgpd" + autoid.toString()), autoid);
	autoid = autoid + 1;
	if (autoid > 4)
	{
		autoid = 0;
	}
}

function do_chg_pd()
{
	pdtt = window.setInterval("chg_pd()", 5000);
}