表单切换，用回车键替换Tab健(不支持IE)

<div>
<form>
<input name="a" tab="1" />
<input name="a" tab="3" />
<input name="a" tab="2" />
<input name="a" tab="5" />
<input name="a" tab="4" />
<input type="submit" value="submit" />
</form>
</div>
<script type="text/javascript">
var inputs = document.getElementsByTagName("input");
for (i = 0; i < inputs.length; i++) {
inputs[i].onkeydown = function(e){
if (e.keyCode == 13) {
var input = getInputByTab(parseInt(this.getAttribute("tab")) + 1);
if (input) {
input.focus();
return false;
}
}
}
}
function getInputByTab(t) {
for (i =0; i < inputs.length; i++) {
if (inputs[i].getAttribute("tab") == t)
return inputs[i];
}
return false;
}
</script>