Text file being written to twice

[adrianpeyton]

Ive got a form that submits a voluntary contribution from staff for a charity fund.
They enter their name, and the amount from a drop down box.
I have it writing to a file, delimited by ";"

Sometimes, 2 new lines of information are written to the file instead of one, so the record is duplicated in the file
eg
"staffname";"10";"euro";"3.1.1.110";"05/12/03";"14.12"
"staffname";"10";"euro";"3.1.1.110";"05/12/03";"14.12"

Can anyone suggest a way to stop this.
I have tested this myself, and I have only pressed the submit image (i have an image button to submit the form) only once

I am stumped!
Thanks
Adrian.

<?php
$datestring = date("d/m/y");
$timestring = date("H.i.s");

//get the IP address of the computer that makes the donation.
if(getenv("HTTP_X_FORWARDED_FOR")){ 
                $ip=getenv("HTTP_X_FORWARDED_FOR"); 
        } 
        else{ 
                $ip=getenv("REMOTE_ADDR"); 
        } 

$fp = fopen("fundlist.txt", "a"); 
// Check if can write to file 
if (!$fp)  { 
       print 'Could not open desired file for writing'; 
} 
$donationvalue = 0;
$name = $HTTP_POST_VARS['name'];
$amount = $HTTP_POST_VARS['amount'];
$currency = $HTTP_POST_VARS['currency'];
$amounteuro = $HTTP_POST_VARS['amounteuro'];
$amountpound = $HTTP_POST_VARS['amountpound'];

if ($currency == "euro") { $donationvalue = ($amounteuro * 10); $currsign = "€";}
if ($currency == "pound") { $donationvalue = ($amountpound * 7); $currsign = "£";}

// Set what will be written to file 
$outputstring = "\"$name\";\"$donationvalue\";\"$currency\";\"$ip\";\"$datestring\";\"$timestring\"\n";
echo $outputstring;

// Finally, write to file 
fwrite($fp, $outputstring); 

// Close the written file 
fclose($fp); 

?>

[paulnaj]

I don't know why this is happening but you could just check to
see if the last line of the file is the same that is going to be
added, and if so, don't write it again.

Also, I noticed something else that might cause you trouble
later:
You test to see if $fp is valid if the 'if' statement. But, later,
whether or not it is valid, you use it.

Probably best to do either ...

// Use die instead of print
if (!$fp)  {  

       die('Could not open desired file for writing');  

}  

... or ...

// Put all the rest in the corresponding 'else' block
if (!$fp)  {  

       print('Could not open desired file for writing');  

}  else {
       // ... all the rest of the file
}