Reloading Page Problem

[Justin Sampson]

Hi,
When you go to http://www.webdevelopershq.com/text2.php3 and add a comment on the next page where it says our joke was added if you reload that page it adds the joke into the database again and again for everytime you reload the page. Is there anyway to stop this?

<?php
// If the user wants to add text
if (isset($addjoke)):
?>
<FORM ACTION="<?php echo($PHP_SELF); ?>" METHOD=POST>
<P>Type your joke here:<BR>
<TEXTAREA NAME="joketext" ROWS=10 COLS=40 WRAP></TEXTAREA>
<BR><INPUT TYPE=SUBMIT NAME="submitjoke" VALUE="SUBMIT"></FORM>


<?php
else:
//connection variables
$dbconnect = mysql_connect("localhost", "user", "password");


//Cannot Connect
if (!$dbconnect) {
echo ("<p>Unable to connect to the database.</p>");
exit();
}


//select database
mysql_select_db("jokes", $dbconnect);

//Cannot find DB
if(! @mysql_select_db("jokes") ) {
echo ("<p>Unable to locate the database at this time.</p>");
exit();
}

echo("<font size='5'><b>Current Comments:</b></font><p>");
//get TheText from test
$result = mysql_query("SELECT Joketext FROM Jokes");

//unable to get TheText
if(!$result) {
echo ("<p>Unable to process database query</p>");
exit();
}

//show the text
while ($row = mysql_fetch_array($result)) {
echo("<table width='600' cellspacing='0' border='1' cellpadding='3' bordercolor='#666666' bgcolor='#DDDDDD'><tr><td width='600'>" . $row["Joketext"] . "</td></tr></table><p>");
}

endif;
?>
<?php
  // If a joke has been submitted,    
  // add it to the database.    
  if ("SUBMIT" == $submitjoke) {
   $sql = "INSERT INTO Jokes SET " .
   "JokeText='$joketext', " .
   "JokeDate=CURDATE()";
   if (mysql_query($sql)) {
   echo("<P>Your joke has been added.</P>");     
    } else {    
	echo("<P>Error adding submitted joke: " .
mysql_error() . "</P>");      }    }
?>


<P><font size="2" face="verdana"><A HREF="<?php echo($PHP_SELF); ?>?addjoke=1">Add Your Jokes!</A><br>
<A HREF="<?php echo($PHP_SELF); ?>">View All The Jokes.</A></font></P>

Thanks,
Justin Sampson

[Son Nguyen]

This is an interesting thing I also want to know.

Since if the visitor reloads, it's like they submit new data (the browser then sends the data again!)

So basically either you have an unique field (which not this case) or check the input with the latest input (which is possible, but not a very nice technic).

So if anyone has a better way, please mention. Thanks

[freddydoesphp]

By adding $submitjoke = "";
It resets the value of $submitjoke to nothing so if the user hits reload the variable $submitjoke will not hold the value "SUBMIT" anymore so it won't add the joke again.


<?php
// If a joke has been submitted,
// add it to the database.
if ("SUBMIT" == $submitjoke) {
$sql = "INSERT INTO Jokes SET " .
"JokeText='$joketext', " .
"JokeDate=CURDATE()";
if (mysql_query($sql)) {
echo("<P>Your joke has been added.</P>");
} else {
echo("<P>Error adding submitted joke: " .
mysql_error() . "</P>");
}
$submitjoke = "";
}

?>

[Son Nguyen]

Nice, Freddy!
Have to add this technique into my note

[jrap]

Although it doesn't make a difference, a 'cleaner' way of what freddy did is using unset

unset($submitjoke);

[freddydoesphp]

Ah why yes, nice call! Built in functions vs hacked code = always better!

[Justin Sampson]

Thanks!
Freddy, I can't get your one to work but robp's works fine?