//日期驗證
function chkDate(datestr) { 
    var year, month, day; 
    var pattern = /^\d{4}\/\d{1,2}\/\d{1,2}$/; 
    var tmpary  = new Array() 
    if (!pattern.test(datestr))  return false; 

    tmpary = datestr.split("/"); 
    year  = tmpary[0]; 
    month = tmpary[1]; 
    day   = tmpary[2]; 

    if (month<1 || month>12 || day>31 || day<1)  return false; 

    if (month == 2 && day > 28) { 
        if ((year%4==0 && year%100!=0) || (year%400==0)) { // ¬°¶|¦~ 
            if (day > 29) return false; 
        } 
        else {  // «D¶|¦~ 
            return false; 
        } 
    } 
    if (day>30 && ((month % 2) == Math.floor(month/8))) return false; 

    return true; 
}