John Keston Classes

Week 2

Session 1: Now we will continue our discussion on some of the fundamentals of cgi (common gateway interface) scripting, commonly refered to as server side scripting. We’ll look at usefully troubleshooting techniques such as phpinfo() and using the echo statement to display variable values. In the lab make the guestbook form populate the guests.txt flat file Set the permissions to world writable and implement the following code:

<?
    $gb_file = fopen( "guests.txt", "a+" );
    if ( fwrite($gb_file, "$name\t$email\n") ) {
        $body  = "My message Text...\n";
        $body .= "$name\n";
        $body .= "$email\n";
        mail( "my_email@my_domain.edu","Guest Book Entry", $body );
        echo "Thanks!<br>\n";
    }
    else {
        echo "could not write file...<br>\n";
    }
?>

You must create a file in the same folder called “guests.txt” for this example to work. It is also necessary to set the permissions so that the file is “world writable”. The permissions can be set using an FTP client. If you’re unsure how to do this we can go over this in class on Session 1. To check your work, view guest.txt in the browser by going to http://<account_name>.aisites.com/guests.txt

Session 2: Now that your guestbook form is adding each new entry to the “guests.txt” file, create a new php document called “show_guests.php”. Write code in the script to loop through the guests.txt file and display the results in HTML. Make the email field a mailto link ( <a href=”mailto:test@test.com”>test@test.com</a> ). Here’s an example of a loop:

Example #1
<?
        $gb_file = file( 'guests.txt' );
        for( $x=0; $x < count($gb_file); ++$x ) {
                echo ( "line $x:" . $gb_file[$x] . "\n" );
        }
?>

Example #2
<?
    $gb_file = file( 'guests.txt' );
    while( list($line_nums, $lines) = each($gb_file) ) {
        echo( "line $line_nums:" . $lines . "\n" );
    }
?>

Download: PHP Problem Set 2
1. All PHP problems within a “set” are due by the beginning of class on the next day that the class meets.
2. Answers must be available via links on the OLS or comparable hosting and copied to the drop off drive.
3. Solutions to each problem set will be given during demonstrations on the day that they are due.
4. Grades will be collected during the solution demonstrations by an assigned classmate.