// JavaScript Document
function checkNum() {
	var original = document.form1.original.value;
	var danwei = document.form1.danwei.value;
		if (original.length == 0)	{
			alert("请输入一个数字。");
			return false;
		}
		if (danwei == "0")	{
			alert("请选择一个单位。");
			return false;
		}
	for (var i=0; i<original.length; i++)
	{
		var ch = original.substring(i, i + 1);
		if (ch!="." && ch!="+" && ch!="-" && ch!="e" && ch!="E" && (ch < "0" || ch > "9"))
		{
			alert("请输入有效的数字。");
			return false
		}
	}
	return true
}
function compute()	{
	var original = document.form1.original.value;
	var danwei = document.form1.danwei.value;
	if (danwei == "1")	{
		var kw = 0.7457122 * original;
		var ps = 1.0141686 * original;
		result = "功率：" + kw.toFixed(2) + "kW 和 " + ps.toFixed(2) + "PS。";
	}
	if (danwei == "2")	{
		var hp = 1.341 * original;
		var ps = 1.360 * original;
		result = "功率：" + hp.toFixed(2) + "hp 和 " + ps.toFixed(2) + "PS。";
	}
	if (danwei == "3")	{
		var hp = 0.9860294 * original;
		var kw = 0.7352941 * original;
		result = "功率：" + hp.toFixed(2) + "hp 和 " + kw.toFixed(2) + "kW。";
	}
	if (danwei == "4")	{
		var usmpg = 0.832 * original;
		var lkm = 282.35 / original;
		result = "油耗：" + usmpg.toFixed(2) + "MPG（美）和 " + lkm.toFixed(2) + "L/100km。";
	}
	if (danwei == "5")	{
		var ukmpg = 1.201 * original;
		var lkm = 235 / original;
		result = "油耗：" + ukmpg.toFixed(2) + "MPG（英）和 " + lkm.toFixed(2) + "L/100km。";
	}
	if (danwei == "6")	{
		var ukmpg = 282.35 / original;
		var usmpg = 235 / original;
		result = "油耗：" + ukmpg.toFixed(2) + "MPG（英）和 " + usmpg.toFixed(2) + "MPG（美）。";
	}
	if (danwei == "7")	{
		var mile = 0.6213712 * original;
		result = "长度：" + mile.toFixed(2) + " 英里。";
	}
	if (danwei == "8")	{
		var km = 1.609344 * original;
		result = "长度：" + km.toFixed(2) + "km。";
	}
	if (danwei == "9")	{
		var nm = 1.3557484 * original;
		result = "扭矩：" + nm.toFixed(2) + "N·m。";
	}
	if (danwei == "10")	{
		var ftlb = 0.7376 * original;
		result = "扭矩：" + ftlb.toFixed(2) + "ft·lb。";
	}
	document.getElementById("results").style.display = 'block';
	document.getElementById("results").style.color = '#CC0000';
	document.getElementById("results").innerText = result;
}