//短日期，形如   (2003-12-05)   
              function   strdatetime(str)   
              {   
                    var   r   =   str.match(/^(\d{1,4})(-|\/)(\d{1,2})\2(\d{1,2})$/);     
                    if(r==null)return   false;     
                    var   d=   new   date(r[1],   r[3]-1,   r[4]);     
                    return   (d.getfullyear()==r[1]&&(d.getmonth()+1)==r[3]&&d.getdate()==r[4]);   
              }   
     // 2.3   长时间，形如   (2003-12-05   13:04:06)   
              function   strdatetime(str)   
              {   
                  var   reg   =   /^(\d{1,4})(-|\/)(\d{1,2})\2(\d{1,2})   (\d{1,2}):(\d{1,2}):(\d{1,2})$/;     
                  var   r   =   str.match(reg);     
                  if(r==null)return   false;     
                  var   d=   new   date(r[1],   r[3]-1,r[4],r[5],r[6],r[7]);     
                  return   (d.getfullyear()==r[1]&&(d.getmonth()+1)==r[3]&&d.getdate()==r[4]&&d.gethours()==r[5]&&d.getminutes()==r[6]&&d.getseconds()==r[7]);   
              }