sample: get values from input type="text" elements
by sii_side
HTML
<form name="Form">
<input type="text" name="a1" value="hoge">
<input type="text" name="a2" value="fuga">
<input type="text" name="a3" value="piyo">
</form>
JavaScript
var r = [];
for(var i = 1; i <= 3; i++) {
r[i - 1] = document.forms["Form"].elements["a" + i].value;
}
window.alert(r);