how to using function auto tab

[minditx]

i have function for generate textbox while user insert some value. what is my problem is how to insert function auto tab in this textbox.

here my javascript code :

function createForm(no_received) {
data = "";
inter = "'";
if (no_received < 300 && no_received > -1) {
for (i=1; i <= no_received; i++) {
if (i < 10) spaces=&quot; &quot;;
else spaces=&quot; &quot;;
data = data + &quot;Serial No &quot;+ &quot; :&quot; + i + spaces
+ &quot;<input type='text' size=20 name= &quot; + inter
+ &quot;url&quot; + i + inter + &quot;'><br>&quot;;
}
if (document.layers) {
document.layers.cust.document.write(data);
document.layers.cust.document.close();
}
else {
if (document.all) {
cust.innerHTML = data;

}
}
}
else {
window.alert(&quot;Please select up to 300 entries.&quot;
}
}

here my textbox code:
<input name=&quot;no_received&quot; type=&quot;text&quot; onChange=&quot;createForm(frmTest.no_received.value);&quot; maxlength=&quot;10&quot; size=&quot;10&quot; >

i'm using function keyup but still did not work.

function autotab(original,destination){
if (original.getAttribute&&original.value.length==original.getAttribute(&quot;maxlength&quot)
destination.focus()
}

how can i join this function with function createform.

thanks you