Hi,
Try with this script.

<script language="javascript">
function txtvalid(intCnt) {
for(intI=1;intI<=intCnt;intI++) {
if(document.getElementById("txt"+intI).value=="") {
alert("Please enter text"+intI);
document.getElementById("txt"+intI).focus();
return false;
}
}
}

function txt(intCnt) {
for(intI=1;intI<=intCnt;intI++) {
document.write("text"+intI+" : <input type='text' name='txt"+intI+"' id='txt"+intI+"' /><br />");
}
}

</script>
<form onsubmit="return txtvalid(3);">
<script>txt(3);</script><br />
<input type="submit" name="btn" value="Submit" />
</form>

just put it in a for loop to get the count-simple.