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Can I determine the number of form elements with a certain name prefix?

Jun 13th, 2000 05:52
Martin Honnen,


You have an unknown number of fields with names
  field0, field1, field2, ...
and want to determine the number of fields:

<HTML>
<HEAD>
<STYLE>
</STYLE>
<SCRIPT>
function numberOfElements(form, prefix) {
  var n = 0;
  var i = 0;
  while (form[prefix + i++])
   n++;
  return n;
}
</SCRIPT>
</HEAD>
<BODY>
<FORM NAME="aForm">
<INPUT TYPE="text" NAME="kibo0">
<INPUT TYPE="text" NAME="kibo1">
<INPUT TYPE="text" NAME="kibo2">
<INPUT TYPE="text" NAME="kibo3">
<BR>
<INPUT TYPE="button" NAME="button0" VALUE="show number of text fields"
       ONCLICK="alert(numberOfElements(this.form, 'kibo'));"
>
<INPUT TYPE="button" NAME="button1" VALUE="show number of buttons"
       ONCLICK="alert(numberOfElements(this.form, 'button'));"
>


</FORM>
</BODY>
</HTML>