javascript做日期选择器实例

                                  
  1.新建selectDateAll.js
  var months = new Array("一月", "二月", "三月","四月", "五月", "六月", "七月", "八月", "九月","十月", "十一月", "十二月");
var daysInMonth = new Array(31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);
var days = new Array("星期日","星期一", "星期二", "星期三", "星期四", "星期五", "星期六");
var getObject,oldObject;//取得当前对象
//取得指定年月的天数
function getDays(month, year) {
   if (1 == month)
      return ((0==year%4)&&(0!=(year%100)))||(0==year%400)?29:28;
   else
      return daysInMonth[month];
}
//取得今天的年,月,日
function getToday() {
   this.now = new Date();
   this.year = this.now.getFullYear();
   this.month = this.now.getMonth();
   this.day = this.now.getDate();
}
today = new getToday();
//创建日历
function newCalendar() {
   today = new getToday();
   var parseYear = parseInt(document.all.year[document.all.year.selectedIndex].text);
   var newCal = new Date(parseYear,document.all.month.selectedIndex, 1);
   var day = -1;
   var startDay = newCal.getDay();
   var daily = 0;
   if ((today.year == newCal.getFullYear()) &&(today.month == newCal.getMonth()))day = today.day;
   var tableCal = document.all.calendar.tBodies.dayList;
   var intDaysInMonth =getDays(newCal.getMonth(), newCal.getFullYear());
   for (var intWeek = 0; intWeek < tableCal.rows.length;intWeek++)
       for (var intDay = 0;intDay < tableCal.rows[intWeek].cells.length;intDay++){
         var cell = tableCal.rows[intWeek].cells[intDay];
  if ((intDay == startDay) && (0 == daily))daily = 1;
  if(day==daily)cell.className = "today";//今天的Class
  else if(intDay==6)cell.className = "sunday";//周六的Class
  else if (intDay==0)cell.className ="satday";//周日的Class
  else cell.className="normal";//平常的Class
  if ((daily > 0) && (daily <= intDaysInMonth)){
   cell.innerText = daily;
   daily++;
  }else cell.innerText = "";
   }
}
//取得鼠标单击处的日期数据
function getDate() {
   var sDate;
   if ("TD" == event.srcElement.tagName)
      if ("" != event.srcElement.innerText){//定义显示日期的格式
sMonth = document.all.month.value;
sDay = event.srcElement.innerText;
if(sMonth.length==1)sMonth = "0"+sMonth;
if(sDay.length==1)sDay = "0"+sDay;
sDate = document.all.year.value + "-" + sMonth + "-" + sDay;
getObject.value=sDate;
window.close();
  }
}
//隐藏图层
function HideLayer() {
Layer.style.visibility = "hidden";
}
//显示图层
function LayerShow(){
Layer.style.visibility = "visible";
}
//显示div对象Layer
function ShowLayer(t,l) {
if(oldObject==null)oldObject=getObject;//赋值
if(Layer.style.visibility != "visible" && oldObject==getObject){//判断是否操作同一表
Layer.style.top = t+document.body.scrollTop;
Layer.style.left = l+document.body.scrollLeft;
Layer.style.visibility = "visible";
oldObject=getObject;
}else if(oldObject==getObject){
HideLayer();
}else{
Layer.style.top = t+document.body.scrollTop;
Layer.style.left = l+document.body.scrollLeft;
Layer.style.visibility = "visible";
oldObject=getObject;
}
}
//定义div对象Layer用以显示日期
function getLayer(){
document.write("<div id=\"Layer\" style=\"position:absolute;width:340;z-index:12;boder-color:#ffffff;border:0px outset white;background-color:#D4D0C8;layer-background-color:#D4D0C8;visibility:hidden;height:38;left:58;top:137;\"><input type=\"hidden\" name=\"ret\"><table width='320' id=\"calendar\" cellpadding=\"0\" align=\"center\"><thead><tr><td height='4'></td></tr><tr><td colspan=7 align=CENTER>请选择月份：<select id=\"month\" onChange=\"newCalendar()\" name=\"select\" class=\"smallSel\">");
for (var intLoop = 0; intLoop < months.length;  intLoop++)
document.write("<OPTION VALUE= " + (intLoop + 1) + " " + (today.month == intLoop ? "Selected" : "") + ">" + months[intLoop]);
document.write("</select> &nbsp;&nbsp;&nbsp;&nbsp;请选择年份：<select id=\"year\" onChange=\"newCalendar()\" name=\"select\" class=\"smallSel\">");
for (var intLoop = today.year-50; intLoop < (today.year + 10); intLoop++)
document.write("<OPTION VALUE= "+intLoop+" "+(today.year == intLoop ?  "Selected" : "") + ">" + intLoop);
document.write("</select></td></tr><tr><td height='6'></td></tr><tr class=\"days\">");
document.write("<TD class=sunday>" + days[0] + "</TD>");
for (var intLoop = 1; intLoop < days.length-1;intLoop++)
document.write("<TD>" + days[intLoop] + "</TD>");
document.write("<TD class=sunday>" + days[intLoop] + "</TD>");
document.write(" </tr></thead><tbody border=1 cellspacing=\"0\" cellpadding=\"0\" id=\"dayList\" align=CENTER ONCLICK='getDate()'>");
for (var intWeeks = 0; intWeeks < 6; intWeeks++){
document.write("<TR style='cursor:hand'>");
for (var intDays = 0; intDays < days.length;intDays++)document.write("<TD></TD>");
document.write("</TR>");
}
document.write("</tbody></table></div>");
}
//定义css
document.write("<style>TABLE{font-family:宋体,SimSun; font-size:9pt;border:0px;bgcolor:#D4D0C8;}.drpdwn {font-family:宋体,SimSun;font-size:9pt;color:#000000;background-color:#000000} SELECT.smallSel{    BACKGROUND-COLOR: #eeeeee;    COLOR: #000000;    FONT-SIZE: 9pt} .normal{BACKGROUND: #D4D0C8;} .today {font-weight:bold;background-image:  url(date.gif);} .satday{color:#800000} .sunday{color:#800000} .days {FONT-SIZE: 9pt;} .Arraw {color:#0000BB; cursor:hand; font-family:Webdings; font-size:9pt}</style>");

getLayer();//显示日期选择器

//选择日期
function selectDate(x){
getObject=x;
newCalendar();
ShowLayer(0,0);//显示出div
}

2 新建selectDate.htm
  <html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>请选择日期</title>
</head>
<script language="JavaScript" src="selectDateAll.js"></script>
<script language="JavaScript">
function returns(){
window.returnValue = dates.value;
}
</script>
<body bgcolor="#d4d0c8"
  leftmargin="0"
  rightmargin="0"
  bottommargin="0"
  topmargin="0"
  onLoad="selectDate(dates)"
  onUnload="returns()">
<input type="hidden" name="dates" id="dates">
</body>
</html>

3 建立index.htm
  <html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>日期选择示例</title>
</head>
<script language="JavaScript">
<!--
function popup(test){
  var xx=event.clientX;
  var yy=event.clientY;
  test.value=window.showModalDialog("selectDate.htm","","dialogWidth:350px;dialogHeight:180px;dialogLeft:"+xx+"px;dialogTop:"+yy+"px;status:0;");
}
-->
</script>
<body>
请输入日期：
<input name="test" id="test" type="text" onClick="popup(this)">
</body>
</html>