avoid special characters???

[kikidonc]

Hi,

I'd like to check what the visitor filled in the form. Does anyone know how to do that, and check in the same time that no unauthorized characters have been typed...

Thank you very much,
Fred.

PS: I'm meanwhile looking for a code that check an e-mail address is correct (at least that contains a name, a @, a domain and an extension like .com, .org, .net, ...).

[webphp]

Fred,
The easiest way to do this would be with javascript form validation. It creates a slightly heavier page to load, but it prevents the page from hitting the server if any of your illegal cases are detected.
Rick

[sardonyx]

While you can use Javascript to check for evil characters, it's not the most reliable way since a user can turn off Javascript.

I recommend that you use HTMLSPECIALCHARS() and/or RAWURLENCODE() to convert all the special characters to html.. check out the function definitions in the PHP references at www.php.net for more details on how those functions work.

[Anon]

If you are using PHP4 try the preg_match function.

(preg_match ("/\W/",$form_field_name))

As for your email create ad the following javascript to your page as a function. In this case call it FormatEmail.

<!--- java script --->

function EmailError (obj) {
return FormError (obj, '"' + obj.value + '" is not a valid email address.');
}

function FormatEmail (obj) {
obj.value = Trim (obj.value);

if (obj.value.length == 0)
	return true;

ndx = 0;
atsign = false;
dot = false;

while (ndx < obj.value.length) {
	if (obj.value.charAt(ndx) == ' ')
		return EmailError (obj);

	if (obj.value.charAt(ndx) == '@') {
		atsign = true;
		++ndx;
		break;
	}

	++ndx;
}

if (!atsign) return EmailError (obj);

while (ndx < obj.value.length) {
	if (obj.value.charAt(ndx) == ' ')
		return EmailError (obj);

	if (obj.value.charAt(ndx) == '.') {
		dot = true;
	}

	++ndx;
}	

if (!dot) return EmailError (obj);

return true;

}

function EmailRequired (obj, msg) {
if (!EditRequired (obj, msg))
return false;

return FormatEmail (obj);	

}

<!--- end of java script --->

Then add the following line to your email input form. onchange="FormatEmail (this);"

Example:

<input onchange="FormatEmail (this);" size="25" name="email">

[kikidonc]

Thank you very much.

Fred.