日历 （IE，FireFox，Safari）

原作者是Oliver Bryant， 我在Ta的基础上修改的，添加了前一年，后一年的选择，修改了事件响应，去掉了过去日期不可选择等。
入口方法是lcs()。返回值是YYYYMMDD。

function getObj(objID)
{
    if (document.getElementById) {return document.getElementById(objID);}
    else if (document.all) {return document.all[objID];}
    else if (document.layers) {return document.layers[objID];}
}

function Left(obj)
{
	var curleft = 0;
	if (obj.offsetParent)
	{
		while (obj.offsetParent)
		{
			curleft += obj.offsetLeft
			obj = obj.offsetParent;
		}
	}
	else if (obj.x)
		curleft += obj.x;
	return curleft;
}

function Top(obj)
{
	var curtop = 0;
	if (obj.offsetParent)
	{
		while (obj.offsetParent)
		{
			curtop += obj.offsetTop
			obj = obj.offsetParent;
		}
	}
	else if (obj.y)
		curtop += obj.y;
	return curtop;
}


// Calendar script
var today = new Date();
var today_m=today.getMonth();//sccm
var today_y=today.getFullYear();//sccy
var cur_m=today.getMonth();//ccm
var cur_y=today.getFullYear();//ccy
var cur_d=today.getDate();
	
function splitDate(sdate) {
	if(!sdate||sdate.length!=8){
		return null;
	}
	curdtarr=new Array(curdt.substring(0,4),curdt.substring(4,6),curdt.substring(6));
	
	for(var k=0;k<curdtarr.length;k++) {
		//alert(curdtarr[k]);
		if (isNaN(curdtarr[k])){			
			return null;
		}
	}
	return curdtarr;
}

document.write('<table id="fc" style="position:absolute;border-collapse:collapse;background:#FFFFFF;border:1px solid #ABABAB;display:none" cellpadding=2>');
document.write('<tr>');
document.write('<td style="cursor:pointer" onclick="csuby()">');
document.write('<a title="last year">');
document.write('<img src="/TCDBWS/resource/ly.gif">');
document.write('</a>');
document.write('</td>');
document.write('<td style="cursor:pointer" onclick="csubm()">');
document.write('<a title="last month">');
document.write('<img src="/TCDBWS/resource/lm.gif">');
document.write('</a>');
document.write('</td>');
document.write('<td colspan=3 id="mns" align="center" style="font:bold 13px Arial">');
document.write('</td>');
document.write('<td align="right" style="cursor:pointer" onclick="caddm()">');
document.write('<a title="next month">');
document.write('<img src="/TCDBWS/resource/nm.gif">');
document.write('</a>');
document.write('</td>');
document.write('<td align="right" style="cursor:pointer" onclick="caddy()">');
document.write('<a title="next year">');
document.write('<img src="/TCDBWS/resource/ny.gif">');
document.write('</a>');
document.write('</td>');
document.write('</tr>');
document.write('<tr><td align=center style="background:#ABABAB;font:12px Arial">S</td><td align=center style="background:#ABABAB;font:12px Arial">M</td><td align=center style="background:#ABABAB;font:12px Arial">T</td><td align=center style="background:#ABABAB;font:12px Arial">W</td><td align=center style="background:#ABABAB;font:12px Arial">T</td><td align=center style="background:#ABABAB;font:12px Arial">F</td><td align=center style="background:#ABABAB;font:12px Arial">S</td></tr>');
for(var kk=1;kk<=6;kk++) {
	document.write('<tr>');
	for(var tt=1;tt<=7;tt++) {
		num=7 * (kk-1) - (-tt);
		document.write('<td id="v' + num + '" style="width:18px;height:18px">&nbsp;</td>');
	}
	document.write('</tr>');
}
document.write('<tr>');
document.write('<td colspan=7 align="center" style="font:bold 13px Arial;cursor:pointer" onclick="closewin()">');
document.write('close');
document.write('</td>');
document.write('</tr>');
document.write('</table>');



var updobj;
function lcs(ielem) {
	updobj=ielem;
	getObj('fc').style.left=Left(ielem);
	getObj('fc').style.top=Top(ielem)+ielem.offsetHeight;
	getObj('fc').style.display='';
	
	// First check date is valid
	curdt=ielem.value;	
	//alert(curdt);
    curdtarr=splitDate(curdt);
	
	if (curdtarr) {
		cur_m=curdtarr[1]-1;
		cur_y=curdtarr[0];
		cur_d=curdtarr[2];
	} else {
		cur_d='';		
	}
	prepcalendar(cur_d,cur_m,cur_y);
	
}



function cs_over(i) {
	var obj =  new Object();
	obj.i=i;
	obj.cs_over=function (){
		////alert(i);
		getObj('v'+i).style.background='#FFCC66';
	}
	return obj;
}

function cs_out(i) {
	var obj =  new Object();
	obj.i=i;
	obj.cs_out=function (){
		////alert(i);
		getObj('v'+i).style.background='#C4D3EA';
	}
	return obj;
}

function cs_click(i) {
	var obj =  new Object();
	obj.i=i;
	obj.doclick=function (){
		////alert(i);
		updobj.value=calvalarr[i]
		closewin();//getObj('fc').style.display='none';
	}
	return obj;
}

function closewin(){
	getObj('fc').style.display='none';
}


var mnn=new Array(31,28,31,30,31,30,31,31,30,31,30,31);
var mnl=new Array(31,29,31,30,31,30,31,31,30,31,30,31);
var calvalarr=new Array(42);

function f_cps(obj) {
	obj.style.background='#C4D3EA';
	obj.style.font='10px Arial';
	obj.style.color='#333333';
	obj.style.textAlign='center';
	obj.style.textDecoration='none';
	obj.style.border='1px solid #6487AE';
	obj.style.cursor='pointer';
}

function f_cpps(obj) {
	obj.style.background='#C4D3EA';
	obj.style.font='10px Arial';
	obj.style.color='#ABABAB';
	obj.style.textAlign='center';
	obj.style.textDecoration='line-through';
	obj.style.border='1px solid #6487AE';
	obj.style.cursor='default';
}

function f_hds(obj) {
	obj.style.background='#FFF799';
	obj.style.font='bold 10px Arial';
	obj.style.color='#333333';
	obj.style.textAlign='center';
	obj.style.border='1px solid #6487AE';
	obj.style.cursor='pointer';
}

// day selected
function prepcalendar(hd,cm,cy) {
	//alert(cy+"-"+cm+"-"+hd);
	var sel_m_f_d=new Date();//selected month first day
	sel_m_f_d.setDate(1);
	sel_m_f_d.setFullYear(cy);
	sel_m_f_d.setMonth(cm);
	//alert(sel_m_f_d);
	wd=sel_m_f_d.getDay();//weekday
	//alert("wd is "+wd);
	getObj('mns').innerHTML=cy + '- ' + (1+cm);
	marr=((cy%4)==0)?mnl:mnn;
	for(var i=1;i<=42;i++) {
		f_cps(getObj('v'+i));
		if ((i >= (wd +1)) && (i<=wd+marr[cm])) {
			//dip=((i-wd < sd)&&(cm==today_m)&&(cy==sccy));
			htd=((hd!='')&&(i-wd==hd));
			//if (dip)
			//	f_cpps(getObj('v'+i));
			//else 
			if (htd)
				f_hds(getObj('v'+i));
			else
				f_cps(getObj('v'+i));

			var ove=cs_over(i);
			getObj('v'+i).onmouseover=ove.cs_over;
			var out=cs_out(i);
			getObj('v'+i).onmouseout=out.cs_out;
			var cli=cs_click(i);
			getObj('v'+i).onclick=cli.doclick;
			
			getObj('v'+i).innerHTML=i-wd;	
			var tm='0'+(1+cm);
			tm=tm.substring(tm.length-2);
			var td='0'+(i-wd);
			td=td.substring(td.length-2);
                            //返回值
			calvalarr[i]=''+cy+tm+td;
		} else {
			getObj('v'+i).innerHTML='&nbsp;';
			getObj('v'+i).onmouseover=null;
			getObj('v'+i).onmouseout=null;
			getObj('v'+i).style.cursor='default';
			}
	}
}

//prepcalendar('',ccm,ccy);
//getObj('fc'+cc).style.visibility='hidden';

function caddm() {
	marr=((cur_y%4)==0)?mnl:mnn;
	
	cur_m+=1;
	if (cur_m>=12) {
		cur_m=0;
		cur_y++;
	}
	
	prepcalendar(cur_d,cur_m,cur_y);
}

function caddy() {
	marr=((cur_y%4)==0)?mnl:mnn;
	
	cur_y++;
	prepcalendar(cur_d,cur_m,cur_y);
}

function csubm() {
	marr=((cur_y%4)==0)?mnl:mnn;
	
	cur_m-=1;
	if (cur_m<0) {
		cur_m=11;
		cur_y--;
	}
	
	prepcalendar(cur_d,cur_m,cur_y);
}

function csuby() {
	marr=((cur_y%4)==0)?mnl:mnn;
	
	cur_y--;
	
	prepcalendar(cur_d,cur_m,cur_y);
}