其中ary为二维数组
var customOptions;
var items = document.all.DDListType.selectedIndex;
var obj = document.getElementById("DDListItems");for (i=obj.options.length-1;i>=0;i--)
{
obj.options.remove(i);
}
for (i=0;i<ary[items].length;i++)
{
customOptions = document.createElement("OPTION");
customOptions.text = ary[items][i];
obj.add(customOptions);
}
此时判断document.all.DDListItems.value为空,可在DDListItems中确实有数值。这是为什么?
var customOptions;
var items = document.all.DDListType.selectedIndex;
var obj = document.getElementById("DDListItems");for (i=obj.options.length-1;i>=0;i--)
{
obj.options.remove(i);
}
for (i=0;i<ary[items].length;i++)
{
customOptions = document.createElement("OPTION");
customOptions.text = ary[items][i];
obj.add(customOptions);
}
此时判断document.all.DDListItems.value为空,可在DDListItems中确实有数值。这是为什么?
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