Ultra novice, a program to add to numbers

aduron

I'm starting with PHP, I have some experience in some arcaic program languages because I studied them while in highschool but I'm a lawyer not and I'm trying to start again as a hobbie, I bought this book "Beginning PHP and MySQL 5" by Gilmore but its not easy to understand.

Right now I want to do this, a program that asks 2 numbers (A and 😎 when posting, the system should returns the result of the addition (A+😎.

I've spent like an hour trying to do this but it isn't working, and as I've seen you post real big codes here, I was wondering if someone could post the correct code for this simple operation.

¡Thanks!

Piranha

I guess that you do it all in HTML? Then you first need a page to get the numbers, and then a page to show the result. The first page could look like this (only the form here).

// page form1.php
<form action="form2.php" method="post">
   <input type="text" name="number1" />
   <input type="text" name="number2" />
   <input type="submit" />
</form>

This is a very basic form. You can make it better, read up on html, form and input for that information. Anyway, on the next page you want to catch the numbers sent, add them and show everything. It could look something like this (again only the basics).

<?php // Starts a php block. It is in php blocks you handle everything with php.
$number1 = $_POST['number1']; // Here you assign the variable $number1 to what you did send in the first form.
$number2 = $_POST['number2']; // Same for $number2. Note that all rows ends with a semicolon.
$result = $number1 + $number2; // Counts and assign the result to $result.

echo "$number1 + $number2 = $result"; // echo is used to print things to the screen. All the variables are automatically replaced when using double quotes".
?> // Ends the php block

Now for your next assignment to really learn it. You should allow the user to insert a third and forth number, addition all the way.

aduron

Thank you very much, I almost did it, I just can't pass a variable from one file to another:

<form action="form2.php" method="post"><p>
   <input type="text" name="number1" /></p><p>
   <input type="text" name="number2" /></p><p>
   <input type="text" name="number3" /></p><p>
   <input type="text" name="number4" /></p>
   <input type="submit" />
</form>

<?php 
$number1 = $_POST['number1']; 
$number2 = $_POST['number2']; 
$number3 = $_POST['number3']; 
$number4 = $_POST['number4'];
GLOBAL $result;
$result = $number1 + $number2 + $number3 + $number4; 
echo "$number1 + $number2 + $number3 + $number4 = $result"; 
?> 
<form action="form3.php" method="post"><p>
	<input type="text" name="number5" /></p><p>
	<input type="text" name="number6" /></p>
	<input type="submit" />
</form>

But then:

<?php
$number5 = $_POST['number5']; 
$number6 = $_POST['number6'];
$result2 = $number5 + $number6 + $result;
echo "$result + $number5 + $number6 = $result2"; 
?>

And it doesn't add $result!!!

Piranha

That is because the variable $result is not saved anywhere. Think about each page load as a program on it own, then you will understand this better.

The easiest way is probably to use a input that is hidden to store it, but the best way is probably using sessions.

NogDog

For advanced study: 😉

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang='en'>
<head>
<meta http-equiv='Content-Type' content='text/html; charset=ISO-8859-1'>
<title>Addition Example</title>
<style type="text/css">
form p {
   margin: 0.3em 0;
}
</style>
</head>
<body>
<form action='<?php echo $_SERVER['PHP_SELF']; ?>' method='POST'>
<fieldset>
<legend>Add These Numbers</legend>
<?php
for($ix=1; $ix<10; $ix++)
{
   echo "<p><label>Value #$ix: <input type='text' name='values[]' size='3'></label></p>\n";
}
?>
<p><input type='submit' value='Add Them Up'></p>
</fieldset>
</form>
<?php
if(is_array($_POST['values']))
{
   echo "<h2>Result:</h2>\n";
   $_POST['values'] = array_filter($_POST['values']);
   printf("<p>%s = %s</p>\n", implode(' + ', $_POST['values']), array_sum($_POST['values']));
}
?>
</body>
</html>