Очень вдумчиво читал..
Такое подходит?
Код:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Untitled</title>
</head>
<script type="text/javascript">
function dynamicSelect(id1, id2) {
if (document.getElementById && document.getElementsByTagName) {
var sel1 = document.getElementById(id1);
var sel2 = document.getElementById(id2);
var clone = sel2.cloneNode(true);
var clonedOptions = clone.getElementsByTagName("option");
refreshDynamicSelectOptions(sel1, sel2, clonedOptions);
sel1.onchange = function() {
refreshDynamicSelectOptions(sel1, sel2, clonedOptions);
}
}
}
function refreshDynamicSelectOptions(sel1, sel2, clonedOptions) {
while (sel2.options.length) {
sel2.remove(0);
}
var pattern1 = /( |^)(select)( |$)/;
var pattern2 = new RegExp("( |^)(" + sel1.options[sel1.selectedIndex].value + ")( |$)");
for (var i = 0; i < clonedOptions.length; i++) {
if (clonedOptions[i].className.match(pattern1) ||
clonedOptions[i].className.match(pattern2)) {
sel2.appendChild(clonedOptions[i].cloneNode(true));
}
}
}
window.onload = function() {
dynamicSelect("Country", "City");
}
Street = new Object;
Street["Moscow"]="Moscow Street";
Street["SPeterburg"]="SPeterburg Street";
Street["Ekaterinburg"]="Ekaterinburg Street";
Street["Kiev"]="Kiev Street";
Street["Sevastopol"]="Sevastopol Street";
Street["Minsk"]="Minsk Street";
Street["Bobruisk"]="Bobruisk Street";
function displaydesc(which, descriptionarray, container){
if (document.getElementById)
document.getElementById(container).innerHTML=descriptionarray[which.value]
}
</script>
<body>
<table width="303" border="1" cellpadding="0" cellspacing="0">
<tr>
<td><form name="form1" method="post">
<select name="Country" id="Country">
<option value="select">Choose Country</option>
<option value="Russia">Russia</option>
<option value="Ukraine">Ukraine</option>
<option value="Belarus">Belarussia</option>
</select>
<select name="City" id="City" size="1" onChange="displaydesc(document.form1.City, Street, 'textcontainer1')">
<option class="select" value="select">Choose Town</option>
<option class="Russia" value="Moscow">Moscow</option>
<option class="Russia" value="SPeterburg">SPeterburg</option>
<option class="Russia" value="Ekaterinburg">Ekaterinburg</option>
<option class="Ukraine" value="Kiev">Kiev</option>
<option class="Ukraine" value="Sevastopol">Sevastopol</option>
<option class="Belarus" value="Minsk">Minsk</option>
<option class="Belarus" value="Bobruisk">Bobruisk</option>
</select>
</form>
<div id="textcontainer1" style="font:12px Arial; background-color: #FFF000";></div></td>
</tr>
</table>
</body>
</html>