電卓
<html>
<head>
<title>電卓</title>
<script language="JavaScript">
<!--
disp = "0";
disp2 = "0";
flag = 0;
function push(val) {
if(val >= 0 && val <= 9) { // 電卓に表示する数列を作成
if(flag == 0) {
disp = val;
disp2 = "0";
flag = 1;
}
else {
disp = disp + val;
disp = parseFloat(disp);
}
}
else if(val == "C") { // クリア
disp = "0";
disp2 = "0";
flag = 0;
}
else {
if(disp) {
switch(flag) { // 計算
case 1:disp2 = parseFloat(disp2) + parseFloat(disp); break;
case 2:disp2 = parseFloat(disp2) - parseFloat(disp); break;
case 3:disp2 = parseFloat(disp2) * parseFloat(disp); break;
case 4:disp2 = parseFloat(disp2) / parseFloat(disp); break;
}
}
if(val == "=") { // 計算方法を記憶
flag = 0;
disp = disp2;
}
else if(val == "+") {
flag = 1;
disp = "";
}
else if(val == "−") {
flag = 2;
disp = "";
}
else if(val == "×") {
flag = 3;
disp = "";
}
else if(val == "÷") {
flag = 4;
disp = "";
}
}
document.form1.disp.value = disp // 電卓に表示
}
//-->
</script>
<style>
<!--
input {
width: 100%;
height: 100%;
font-size: 30px;
}
.disp {
text-align: right;
font-size: 35px;
}
//-->
</style>
</head>
<body>
<form name="form1" action="" method="">
<table width="250" height="250" border="1" bordercolor="#000000" cellspacing="0" cellpadding="0">
<tr>
<td colspan="4"><input type="text" name="disp" class="disp" value="0"></td>
</tr>
<tr>
<td width="25%"><input type="button" value="7" onClick="push(this.value)"></td>
<td width="25%"><input type="button" value="8" onClick="push(this.value)"></td>
<td width="25%"><input type="button" value="9" onClick="push(this.value)"></td>
<td width="25%"><input type="button" value="÷" onClick="push(this.value)"></td>
</tr>
<tr>
<td><input type="button" value="4" onClick="push(this.value)"></td>
<td><input type="button" value="5" onClick="push(this.value)"></td>
<td><input type="button" value="6" onClick="push(this.value)"></td>
<td><input type="button" value="×" onClick="push(this.value)"></td>
</tr>
<tr>
<td><input type="button" value="1" onClick="push(this.value)"></td>
<td><input type="button" value="2" onClick="push(this.value)"></td>
<td><input type="button" value="3" onClick="push(this.value)"></td>
<td><input type="button" value="−" onClick="push(this.value)"></td>
</tr>
<tr>
<td><input type="button" value="0" onClick="push(this.value)"></td>
<td><input type="button" value="C" onClick="push(this.value)"></td>
<td><input type="button" value="=" onClick="push(this.value)"></td>
<td><input type="button" value="+" onClick="push(this.value)"></td>
</tr>
</table>
</form>
</body>
</html>
〔 実行する 〕