[Undefined Index Issue.]

Thankyou very much!!

[Undefined Index Issue.]

Hi guys, I'm brand new to PHP, and this type of coding. I've been working on a simple example from a tutorial where a form is used to update information on the same page;
[i]
<form name="form1" method="post" action="<?php echo $_SERVER['PHP_SELF']; ?>">
<input type="text" name="textfield">
<input type="submit" name="Submit" value="Submit">
</form>

<?PHP
echo $_POST['textfield'];
?>[/i]
However, i get the notice :" Undefined index: textfield in E:\web\northey\test6.php on line 14" when the form is first run - after a value has been submitted this goes, so it all works but i suffer from this unsightly error.

I guess i need to somehow define $_post['textfield'] originally, but however i try to do this it either overrules the value comming in from the form, or appears to do nothing but duplicate the above error.

Sorry for being a total No0b - I've searched and searched for a solution and am my wits end.
PS the URL is [a href=\"http://www.northey.net/test6.php\" target=\"_blank\"]http://www.northey.net/test6.php[/a] and ive enabled phpinfo() to help out.