js file

function loadPage(xNum){
	var ht = "700";
	var wd = "700";
	pagesArray = new Array('APB_161-175.swf','APB_176-190.swf','APB_191-205.swf','APB_206-220.swf','APB_221-235.swf','APB_236-250.swf','APB_251-265.swf','APB_266-280.swf','APB_281-295.swf','APB_296-310.swf','APB_311-325.swf','APB_326-340.swf','APB_341-355.swf','APB_356-370.swf','APB_371-385.swf','APB_386-400.swf','APB_401-415.swf','APB_416-430.swf','APB_431-448.swf');
	pageName = pagesArray[xNum];
	document.getElementById('vertualBookOuter').style.display="block";
	//document.getElementById('flashPage').src='./book/port-maps/' + pageName;
	document.frames['flashPage'].window.location='./book/port-maps/' + pageName;
	document.getElementById('pageXNum').value=xNum;
}

html file

<div id="vertualBookOuter">
		<div id="vertualBookInner">
			<div class="vertualBookNav">
				<a href="javascript:flashPageCtrl('pre')">&lt;-- Previous</a> | <a href="javascript:flashPageCtrl('clo')">Close</a> | <a href="javascript:flashPageCtrl('nex')">Next --&gt;</a>
			<input type="hidden" id="pageXNum" value="" />
		</div>
		<div>
			<iframe id="flashPage"></iframe>
		</div>
		<div>
			<a href="javascript:flashPageCtrl('pre')">&lt;-- Previous</a> | <a href="javascript:flashPageCtrl('clo')">Close</a> | <a href="javascript:flashPageCtrl('nex')">Next --&gt;</a>
		</div>
	</div>
</div>

the function is called from a dropdown

<select onchange="loadPage(this.value)">