Need help php beginner!

TheShellBullet

hello all! im trying to make a webpage that asks a user to input two numbers and then showing an average between them. this is what i got so far...

<html>
<head>
<title>Average of 2 numbers</title>
</head>
<body>
<form>
<form method="post">
Number 1: <input type="text" name="number1" /><br />
Number 2: <input type="text" name="number2" /><input type="submit" value="Submit">
</form>

<?php

$average = ($POST['number1'] + $POST['number2']) / 2;
echo $average;
?>
</body>
</html>

can anyone tell me what im doing wrong?

Bjom

look at this tutorial

Ashley_Sheridan

Well, firstly you're trying to include PHP in your HTML code, that's not how it works. What you should be doing is including HTML in your PHP. It sounds like I'm just being picky, but when you think about it that way round you'd be surprised how many problems can be figured out!

Basically, there are a few issues with the code as is. The values coming from $_POST are strings, not numbers, so you could do with using something like this on them:

$average = (floatval($_POST['number1']) + floatval($_POST['number2']) / 2;

Also, you can't use those values until they've actually been sent to the server (PHP is executed on the server, not in the browser) so you chould wrap the two lines of PHP code there in an if statement to check if they have been set or not:

if(isset($_POST['number1']) && isset($_POST['number2']))
{
    $average = (floatval($_POST['number1']) + floatval($_POST['number2']) / 2;
    echo $average;
}

Lastly, as you've not said exactly what was wrong (or even if you had any issue) I am assuming that you are seeing some output and that PHP is set up correctly on your server? If not, make sure to check several things: a) your server is set up for PHP & b) your script has a .php extension and not a .html one.

TheShellBullet

Thanks Ashley, after seeing what you said i tryed to fix my code, and i got this

<html>
<head>
<title>Average of 2 numbers</title>
</head>
<body>
<form>
<form method="post">
Number 1: <input type="text" name="number1" /><br />
Number 2: <input type="text" name="number2" /><input type="submit" value="Submit">
</form>

<?php

$average = (floatval($_POST['number1']) + floatval($_POST['number2']) / 2; 
if(isset($_POST['number1']) && isset($_POST['number2'])) 
{ 
    $average = (floatval($_POST['number1']) + floatval($_POST['number2']) / 2; 
    echo $average; 
} 
?>
</body>
</html>

but now i get this Error "Parse error: syntax error, unexpected ';' in /home/me/public_html/average.php on line 14"

And the problem i was experiencing before, was that when you try to average two input numbers it would always show 0. sorry i dident put that in my original post. 🙁

bradgrafelman

First off, get rid of the first $average line. Why are you trying to define it twice (with the first being outside of the if() statement that makes sure the variables you're about to use actually exist)?

Second, on the other identical line, you've got an unclosed ')' parenthesis.

Ashley_Sheridan

That was my bad, he copied the code verbatim from my posting, and I wrote it in haste without actually testing anything!

bradgrafelman

I'd say the secondary problem was that:

he copied the code

instead of reading it, understanding it, and then writing the solution himself. 😉

TheShellBullet

Im sorry for not being able to grasp this but the code wont show a answer.

<html>
<head>
<title>Average of 2 numbers</title>
</head>
<body>
<form>
<form method="post">
Number 1: <input type="text" name="number1" /><br />
Number 2: <input type="text" name="number2" /><input type="submit" value="Submit">
</form>

<?php

if(isset($_POST['number1']) && isset($_POST['number2'])) 
{ 
    $average = floatval($_POST['number1']) + floatval($_POST['number2']) / 2; 
    echo $average; 
} 
?>
</body>
</html>

bradgrafelman

You've got two <form> elements.

EDIT: You also have the wrong math now. If you input numbers 1 and 2, you're telling PHP to do "1 + 2 / 2" which is "1 + 1" which is "2", which is not the average of 1 and 2.