Displaying Information & Variables PHP Tutorial

The Basics Of IF

If statements are used to compare two values and carry out different actions based on the results of the test. If statements take the form IF, THEN, ELSE. Basically the IF part checks for a condition. If it is true, the then statement is executed. If not, the else statement is executed.

IF Strucure

The structure of an IF statement is as follows:

IF (something == something else)
{
THEN Statement
} else {
ELSE Statement
}

In the last parts of this tutorial I have showed you how to deal with text and variables in PHP and how you can use IF statements to compare them and to make decisions. In this part I am going to show you how to use another important part of PHP, loops.

The WHILE Loop

The WHILE loop is one of the most useful commands in PHP. It is also quite easy to set up and use. A WHILE loop will, as the name suggests, execute a piece of code until a certain condition is met.

Repeating A Set Number Of Times

If you have a piece of code which you want to repeat several times without retyping it, you can use a while loop. For instance if you wanted to print out the words "Hello World" 5 times you could use the following code:

$times = 5;
$x = 0;
while ($x < $times) {
echo "Hello World";
++$x;
}

The Mail Command

Mail is extremely easy to send from PHP, unlike using scripting languages which require special setup (like CGI). There is actually just one command, mail() for sending mail. It is used as follows:

mail($to,$subject,$body,$headers);

In this example I have used variables as they have descriptive names but you could also just place text in the mail command. Firstly, $to. This variable (or section of the command) contains the e-mail address to which the mail will be sent. $subject is the section for the subject of the e-mail and $body is the actual text of the e-mail.

The section $headers is used for any additional e-mail headers you may want to add. The most common use of this is for the From field of an e-mai but you can also include other headers like cc and bcc.

Sending An E-mail

Before sending your mail, if you are using variables, you must, of course, set up the variable content beforehand. Here is some simple code for sending a message:

$to = "php@gowansnet.com";
$subject = "PHP Is Great";
$body = "PHP is one of the best scripting languages around";
$headers = "From: webmaster@gowansnet.com\n";
mail($to,$subject,$body,$headers);
echo "Mail sent to $to";

This code will acutally do two things. Firstly it will send a message to php@gowansnet.com with the subject 'PHP Is Great' and the text:

PHP code is executed on the server, and the plain HTML result is sent to the browser.


Basic PHP Syntax
A PHP scripting block always starts with . A PHP scripting block can be placed anywhere in the document.

On servers with shorthand support enabled you can start a scripting block with .

For maximum compatibility, we recommend that you use the standard form (
?>

A PHP file normally contains HTML tags, just like an HTML file, and some PHP scripting code.

Below, we have an example of a simple PHP script which sends the text "Hello World" to the browser:




echo "Hello World";
?>