取得下拉框的选择数据

	var zone=document.getElementById("zoneId");
	var area=document.getElementById("areaId");
	var build=document.getElementById("buildId");
	var unit=document.getElementById("unitId");
	
	var zoneName = zone.options[zone.selectedIndex].text;
	var areaName = area.options[area.selectedIndex].text;
	var buildName = build.options[build.selectedIndex].text;
	var unitName = unit.options[unit.selectedIndex].text;