resetting a variable



when passing a variable via


or within a form statement

<input type="text" name="mailin">

how do I clear the variable mailin to equal NULL or reset it to nothing?
while still within the program

Thanks for anyones help :)
Thanks alot....

Just so I am clear on this...

lets say I used the command

$name = $_REQUEST['mailin'];

would I issue a

unset($name); or

LOL I suppose I can just try it .... thanks
You will make unset($name);!
But you still able to assign mailin to another variable! It still alive til the end of the pages's process!
Actually after rethinking my question

I guess what I really need is to reset a Cell

for instance I have

if such and such
echo " <TD>hi there<TD>";
echo "<TD>not here</TD>";

so my onclick is where is would reset it
Not sure about what you really want to do, but you can use something like this instead:
if (whatever)[ 
$var =  "<td>hi there</td>"; 
$var =  "<td>not here</td>";
echo $var;
This way you have the content in a variable witch you can work with!

BTW: You said onClink !?
Never forget this: php is a server-side scripting, instead of javascript or html witch are client-side ...