you could check if the value returned from CGI->param('fieldname') is empty by using the length function 
if length($cgi->param('fieldname')) == 0 (that means the field is empt
+y.)

[download]
To check if the value is 0, how about : 
  if ($CGI->param('fieldname') == 0)...

[download]
Option 2: if u want to use Javascript, then this might work: 
<html
<head>
<script language="Javascript">
function chkinput(objForm) {
 if (objForm.inputfield.value == "") {
     objForm.fld_has_value_or_not.value = "N"
  } else {
     objForm.fld_has_value_or_not.value = "Y"
  }
  objForm.submit();
  return true;

}
</script>
</head>
<body>
<form name="testfrm" method="post" action="cgifile.cgi" onSubmit="retu
+rn chkinput(this);">
<input type=hidden name=fld_has_value_or_not value="">
<input type="text" name="inputfield" value="">
<input type=submit value="Submit">
</form>
</body>
</html>

[download]
in this case, if the input field is empty, the hidden variable will be set to "Y", which can be checked by the cgi file and processed accordingly...
hth...

In reply to Re: zero vs. empty by screamingeagle
in thread zero vs. empty by gwhite

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