<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv= " Content-Type " content= " text/html; charset=utf-8 " />
<title>定義函數</title>
</head>
<body>
<input type= " number " id= " one " value= " 2 " name= " one ">
< select id= " sel " >
<option value= ' + '>+</option>
<option value= ' - '>-</option>
<option value= ' * '>*</option>
<option value= ' / '>/</option>
</ select>
<input type= " number " id= " two " value= " 4 " name= " two "/>=
<input type= " text " id= " res " disabled/>
<input type= " button " value= " 計算 " onclick= " sub2() " />
<style>
input{
width:50px;
}
</style>
<script type= " text/javascript ">
function sub2() // 定義函數
{
var onen =parseInt(document.getElementById( " one ").value, 10);
var twon =parseInt(document.getElementById( " two ").value, 10);
var seln =document.getElementById( " sel ").value;
// var resn =document.getElementById("res").value;
if(seln== " + "){
sub=onen+twon;
}
else if(seln== " - "){
sub=onen-twon;
}
else if(seln== " * "){
sub=onen*twon;
}
else{
sub=onen/twon;
}
document.getElementById( " res ").value=sub;
}
</script>
</body>
</html>
<html>
<head>
<meta http-equiv= " Content-Type " content= " text/html; charset=utf-8 " />
<title>定義函數</title>
</head>
<body>
<input type= " number " id= " one " value= " 2 " name= " one ">
< select id= " sel " >
<option value= ' + '>+</option>
<option value= ' - '>-</option>
<option value= ' * '>*</option>
<option value= ' / '>/</option>
</ select>
<input type= " number " id= " two " value= " 4 " name= " two "/>=
<input type= " text " id= " res " disabled/>
<input type= " button " value= " 計算 " onclick= " sub2() " />
<style>
input{
width:50px;
}
</style>
<script type= " text/javascript ">
function sub2() // 定義函數
{
var onen =parseInt(document.getElementById( " one ").value, 10);
var twon =parseInt(document.getElementById( " two ").value, 10);
var seln =document.getElementById( " sel ").value;
// var resn =document.getElementById("res").value;
if(seln== " + "){
sub=onen+twon;
}
else if(seln== " - "){
sub=onen-twon;
}
else if(seln== " * "){
sub=onen*twon;
}
else{
sub=onen/twon;
}
document.getElementById( " res ").value=sub;
}
</script>
</body>
</html>