<!doctype html public "-//w3c//dtd xhtml 1.0 transitional//en" "http://www.w3c.org/tr/xhtml1/dtd/xhtml1-transitional.dtd">
<html xmlns="http://www.w3x.org/1999/xhtml">
<head>
<title>Javascript Day01</title>
<meta http-equlv="content-type" content="text/html;charset=utf-8"/>
<script language="javascript" src="js_demo1.js" type="text/javascript"></script>
<script language="javascript" type="text/javascript">
function firstMethod(){
alert("Hello World in script block.");
}
</script>
</head>
<form>
<h2>1.Hello Word</h2>
<input type="button" value="first button" onclick="alert('Hello Word');"/>
<input type="button" value="second button" onclick="firstMethod();"/>
<input type="button" value="third button" onclick="secondMethod();"/>
<h2>2.判断数据类型，并计算平方</h2>
<input type="text" id="txtData"/><br/>
<input type="button" value="计算平方" onclick="getSquare()";/>
<h2>3.猜数字</h2>
请录入猜测的数字（1-20之间的整数）：<br/>
<input id="txtNumber" type="text" onblur="guessNumber()";/>
</form>
</body>
</html>
js:
function secondMethod(){
alert("hello world");
}
function getSquare(){
var str = document.getElementById("txtData").value;
if(isNaN(str))
alert("请录入数值");
else{
var data=parseFloat(str);
var result = data* data;
alert(result);
}
}
//猜数字
function guessNumber(){
var result = 10;
//得到用户的录入
var str = document.getElementById("txtNumber").value;
//比较
if(isNaN(str))
alert("请录入数值");
else{
var data = parseFloat(str);
var info = data > result ?"大了":"小了";
info = data == result ? "猜对了":info;
alert(info);
}
}