Membuat Perhitungan dengan JavaScript

Contoh:

+ - * /

Untuk Scriptnya copy di bawah ini:

<script language="JavaScript" type="text/javascript">

<!--

function hitung(){

var x=eval(document.form1.x.value);

var y=eval(document.form1.y.value);

var pil= document.form1.opt.value;

if (pil == "tambah") {

var z = x + y;

}

else if (pil == "kurang") {

var z = x - y;

}

else if (pil == "kali") {

var z = x * y;

}

else if (pil == "bagi") {

var z = x / y;

}

document.form1.hasil.value = z;

}

function resetForm(){

document.form1.reset();

}

//-->

</script>

<form name="form1" action="#">

<input type="text" name="x" />

<select name="opt">

<option value="tambah"> + </option>

<option value="kurang"> - </option>

<option value="kali"> * </option>

<option value="bagi"> / </option>

</select>

<input type="text" name="y" />

<input type="button" value="=" onClick="hitung()" />

<input type="text" name="hasil" disabled="true" /><br/>

<input type="button" value="Reset" onClick="resetForm()" />

</form>