function RunNian(The_Year)
{
 if ((The_Year%400==0) || ((The_Year%4==0) && (The_Year%100!=0)))
  return true;
 else
  return false;
}
function GetWeekday(The_Year,The_Month)
{
 
 var Allday;
 Allday = 0;
 if (The_Year>2000)
 {
  
  for (i=2000 ;i<The_Year; i++) 
   if (RunNian(i)) 
    Allday += 366;
   else
    Allday += 365;
  for (i=2; i<=The_Month; i++)
  {
   switch (i)
   {
    case 2 : 
     if (RunNian(The_Year))
      Allday += 29;
     else
      Allday += 28;
     break;
    case 3 : Allday += 31; break;
    case 4 : Allday += 30; break;
    case 5 : Allday += 31; break;
    case 6 : Allday += 30; break;
    case 7 : Allday += 31; break;
    case 8 : Allday += 31; break;
    case 9 : Allday += 30; break;
    case 10 : Allday += 31; break;
    case 11 : Allday += 30; break;
    case 12 :  Allday += 31; break;
    
   }
   
  }
 }
 
 return (Allday+6)%7;
 

}

function chooseday(The_Year,The_Month,The_Day)
{
 var Firstday;
 var completely_date;
 if (The_Day!=0)
  completely_date = The_Year + "-" + The_Month + "-" + The_Day;
 else
  completely_date = "No Choose";
 //showdate 只是一个为了显示而采用的东西，
 //如果外部想引用这里的时间，可以通过使用 completely_date引用完整日期
 //也可以通过The_Year,The_Month,The_Day分别引用年，月，日
 //当进行月份和年份的选择时，认为没有选择完整的日期
 
 Firstday = GetWeekday(The_Year,The_Month);
 ShowCalender(The_Year,The_Month,The_Day,Firstday);
 
}

function nextmonth(The_Year,The_Month)
{
 if (The_Month==12)
  chooseday(The_Year+1,1,0);
 else
  chooseday(The_Year,The_Month+1,0);
}

function prevmonth(The_Year,The_Month)
{
 if (The_Month==1)
  chooseday(The_Year-1,12,0);
 else
  chooseday(The_Year,The_Month-1,0);
}

function prevyear(The_Year,The_Month)
{
 chooseday(The_Year-1,The_Month,0);
}

function nextyear(The_Year,The_Month)
{
 chooseday(The_Year+1,The_Month,0);
}

 

 

function ShowCalender(The_Year,The_Month,The_Day,Firstday)
{

 var showstr;
 var Month_Day;
 var ShowMonth;
 var today;
 today = new Date();
 
 
 
 switch (The_Month)
 {
  case 1 : ShowMonth = "1月"; Month_Day = 31; break;
  case 2 :
   ShowMonth = "2月";
   if (RunNian(The_Year))
    Month_Day = 29;
   else
    Month_Day = 28;
   break;
  case 3 : ShowMonth = "3月"; Month_Day = 31; break;
  case 4 : ShowMonth = "4月"; Month_Day = 30; break;
  case 5 : ShowMonth = "5月"; Month_Day = 31; break;
  case 6 : ShowMonth = "6月"; Month_Day = 30; break;
  case 7 : ShowMonth = "7月"; Month_Day = 31; break;
  case 8 : ShowMonth = "8月"; Month_Day = 31; break;
  case 9 : ShowMonth = "9月"; Month_Day = 30; break;
  case 10 : ShowMonth = "10月"; Month_Day = 31; break;
  case 11 : ShowMonth = "11月"; Month_Day = 30; break;
  case 12 : ShowMonth = "12月"; Month_Day = 31; break;
   
 }
 
 
 showstr = "";
 showstr = "<Table cellpadding=3 cellspacing=0 border=0 bordercolor=#ffffff bgcolor=#ffffff width=180px align=center valign=top style=font-size:12px>"; 
 showstr +=  "<tr><td width=0 style='cursor:hand' onclick=prevyear("+The_Year+"," + The_Month + ")><input type='button' value='<<' ></td><td>" + The_Year + "</td><td width=0 onclick=nextyear("+The_Year+","+The_Month+")  style='cursor:hand'><input type='button' value='>>'></td><td width=0 style='cursor:hand' onclick=prevmonth("+The_Year+","+The_Month+")><input type='button' value='<<'></td><td width=40 align=center>" + ShowMonth + "</td><td width=0 onclick=nextmonth("+The_Year+","+The_Month+")  style='cursor:hand'><input type='button' value='>>'></td></tr>";
 showstr +=  "<tr><td align=center width=100% colspan=6>";
 showstr +=  "<table cellpadding=4 cellspacing=0 border=0 bordercolor=#5c6931 width=180px style=font-size:12px>";
 showstr += "<Tr align=center> ";
    showstr += "<td bgcolor=#5c6931 height=20><strong><font color=#ffffff>日</font></strong></td>";
    showstr += "<td bgcolor=#5c6931 ><strong><font color=#ffffff>一</font></strong></td>";
    showstr += "<td bgcolor=#5c6931 ><strong><font color=#ffffff>二</font></strong></td>";
    showstr += "<td bgcolor=#5c6931 ><strong><font color=#ffffff>三</font></strong></td>";
    showstr += "<td bgcolor=#5c6931 ><strong><font color=#ffffff>四</font></strong></td>";
    showstr += "<td bgcolor=#5c6931 ><strong><font color=#ffffff>五</font></strong></td>";
    showstr += "<td bgcolor=#5c6931 ><strong><font color=#ffffff>六</font></strong></td>";
 showstr += "</Tr><tr>";
 
 for (i=1; i<=Firstday; i++)
  showstr += "<Td align=center  height=18>&nbsp;</Td>";
 
 for (i=1; i<=Month_Day; i++)
 {
  if ((The_Year==today.getYear()) && (The_Month==today.getMonth()+1) && (i==today.getDate()))
   bgColor = "#FFCCCC";
  else
   bgColor = "#ffffff";
  
  if (The_Day==i) bgColor = "#FFFFCC";
  showstr += "<td align=center bgcolor=" + bgColor + " style='cursor:hand' onclick=chooseday(" + The_Year + "," + The_Month + "," + i + ")>" + i + "</td>";
  Firstday = (Firstday + 1)%7;
  if ((Firstday==0) && (i!=Month_Day)) showstr += "</tr><tr>";
 }
 if (Firstday!=0) 
 {
  for (i=Firstday; i<7; i++) 
   showstr += "<td align=center bgcolor=#ffffff>&nbsp;</td>";
  showstr += "</tr>";
 }
  
 showstr += "</tr></table></td></tr></table>";
 cc.innerHTML = showstr;  
 

}