关于下拉列表的问题 <select name="id"> ....</select>alert(document.forms[0].id.length); 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 option 没有length这个属性啊用这个吧 select.length sel1.options.length中只要sell是一个select对象那么你的语句就是正确的,可能是其它地方的问题吧,试找找别的原因看看 我是在一个函数中使用options时候报错的(记得最开始没有报错,后来不知道怎么就报错了),具体代码如下,大家看看哪里有错:<%ResultSet rs=null;ResultSet rs2=null;int count=0;String y2no1=null;String y3no1=null;String vcno1=null;String cdno1=null;String acno1=null;%><script language="JavaScript"><!-- Beginvar arrY2NO = new Array();var arrY3NO = new Array();var arrVCNO = new Array();var arrCDNO = new Array();var arrACNO = new Array();<%String strSQL1="select * from BUGET_CARD" ; rs=selectData1.getSelectData(strSQL1);while(rs.next()){count++;y2no1=rs.getString("Y2NO").trim();y3no1=rs.getString("Y3NO").trim();vcno1=rs.getString("VCNO").trim();cdno1=rs.getString("CDNO").trim();acno1=rs.getString("ACNO").trim();%>arrY2NO[<%=count%>]=<%="\""+y2no1+"\""%>;;arrY3NO[<%=count%>]=<%="\""+y3no1+"\""%>;;arrVCNO[<%=count%>]=<%="\""+vcno1+"\""%>;;arrCDNO[<%=count%>]=<%="\""+cdno1+"\""%>;;arrACNO[<%=count%>]=<%="\""+acno1+"\""%>;;<% }rs.close();%>function selectChange(control, controlToPopulate, ItemArray,GroupArray){var myEle ;var x ;for (var q=controlToPopulate.options.length;q>=0;q--){controlToPopulate.options[q]=null;}myEle = document.createElement("option") ;myEle.value = 0 ;myEle.text = "[SELECT]" ;controlToPopulate.add(myEle) ;for ( x = 1 ; x < ItemArray.length; x++ ){ if ( ItemArray[x] == control.value ){myEle = document.createElement("option") ;myEle.value = x;myEle.text=GroupArray[x];controlToPopulate.add(myEle) ; } }}// End --></script> 新手请教一下问题!!启动tomcat的时候出来的那些严重信息是怎么回事!!!谢谢!! 非计算机专业的培训生何去何从(求建议,谢谢!) struts 跳转 模式窗口打开跳转回主窗体 求日期算法 怎樣算出某年某月的最后一天? 急!显示数据库中图片问题,在线等! 在线急求 一個jdk編譯的問題! 一个比较基础的问题 spring实战 学习的一点疑惑 请各位大虾帮忙,在applet和jsp中如何得到用户的IP地址 菜菜问题,高分相送!!!!!!!!!!!!!
用这个吧 select.length
<%
ResultSet rs=null;
ResultSet rs2=null;
int count=0;
String y2no1=null;
String y3no1=null;
String vcno1=null;
String cdno1=null;
String acno1=null;
%><script language="JavaScript">
<!-- Begin
var arrY2NO = new Array();
var arrY3NO = new Array();
var arrVCNO = new Array();
var arrCDNO = new Array();
var arrACNO = new Array();
<%
String strSQL1="select * from BUGET_CARD" ;
rs=selectData1.getSelectData(strSQL1);
while(rs.next())
{
count++;
y2no1=rs.getString("Y2NO").trim();
y3no1=rs.getString("Y3NO").trim();
vcno1=rs.getString("VCNO").trim();
cdno1=rs.getString("CDNO").trim();
acno1=rs.getString("ACNO").trim();
%>
arrY2NO[<%=count%>]=<%="\""+y2no1+"\""%>;;
arrY3NO[<%=count%>]=<%="\""+y3no1+"\""%>;;
arrVCNO[<%=count%>]=<%="\""+vcno1+"\""%>;;
arrCDNO[<%=count%>]=<%="\""+cdno1+"\""%>;;
arrACNO[<%=count%>]=<%="\""+acno1+"\""%>;;
<%
}rs.close();
%>
function selectChange(control, controlToPopulate, ItemArray,GroupArray)
{
var myEle ;
var x ;
for (var q=controlToPopulate.options.length;q>=0;q--)
{
controlToPopulate.options[q]=null;
}
myEle = document.createElement("option") ;
myEle.value = 0 ;
myEle.text = "[SELECT]" ;
controlToPopulate.add(myEle) ;
for ( x = 1 ; x < ItemArray.length; x++ )
{
if ( ItemArray[x] == control.value )
{
myEle = document.createElement("option") ;
myEle.value = x;
myEle.text=GroupArray[x];
controlToPopulate.add(myEle) ;
}
}
}
// End -->
</script>