Invision Power Services > PHP: Hello World

FυsE

Jul 9 2005, 11:57 PM

PHP is a language that uses basic classes and functions.

Here is a demonstration on how to say "Hello World".

CODE

<?php
$text = "Hello World";
echo($text);

?>

CODE

<?php

     class hello {

     function auto_run() {
         $this->hello_world();
     }

     function hello_world() {
         echo($this->text());
     }

     function text() {
         return "Hello World";
     }

}
?>

CODE

<?php
echo("Hello World");
?>

Scyth

Jul 10 2005, 12:03 AM

Great, I'm sure matt can use this in IPB 2!

Tommeh.

Jul 10 2005, 12:04 AM

QUOTE(.Cole @ Jul 10 2005, 12:57 AM)

PHP is a language that uses basic classes and functions.

Here is a demonstration on how to say "Hello World".
...

CODE

<?php
echo("Hello World"};
?>

oops, you've got a parser error there, the } should be a ), and you can also miss out the brackets as echo is a language construct, not a function

Stephen

Jul 10 2005, 12:05 AM

FυsE

Jul 10 2005, 12:48 AM

ahahah Lol, this wasnt designed for matt, this was designed to help people who are starting to learn PHP should know the basics

Brendon Koz

Jul 10 2005, 01:38 AM

Thanks for the added reference material, Cole.

As far as efficiency goes, however, creating multiple functions calls to do such a simple task might be useful (as in creating the auto_run() can then call multiple functions if updates were needed later on in the class' lifecycle), but will create more processor usage for stack calls.

Also, with efficiency in mind, since echo is a language construct (as already stated), removing the ()'s from the call will lessen the bytes required on the server (hosting space), require the PHP engine to parse that much less text, and look a bit cleaner.

^ Also for reference...

Phil Mossop

Jul 10 2005, 09:06 AM

QUOTE(.Tom @ Jul 10 2005, 01:04 AM)

oops, you've got a parser error there, the } should be a ), and you can also miss out the brackets as echo is a language construct, not a function

Here also:

CODE

echo($this->text};

_

Jul 10 2005, 10:25 AM

CODE

function auto_run() {
hello_world();
}

Internal class functions must be called as $this->...

Ruben K.

Jul 10 2005, 11:36 AM

note that auto_run() is not a constructor

Rikki

Jul 10 2005, 11:51 AM

QUOTE(.Cole @ Jul 10 2005, 12:57 AM)

CODE

...
     function hello_world() {
         echo($this->text};
     }

     function text() {
         return "Hello World";
     }

}
?>

Also you are echoing $this->text which is a property but I assume you meant to call the method $this->text().

bılʞ

Jul 10 2005, 12:17 PM

QUOTE(.Cole @ Jul 10 2005, 01:48 AM)

ahahah Lol, this wasnt designed for matt, this was designed to help people who are starting to learn PHP should know the basics

It would probably help if you knew the basics beforehand.

Wombat

Jul 10 2005, 12:18 PM

If you are going to use OOP at least make the class reusable, otherwise there's little point in bothering.

CODE

<?php

class StringPrinter {

   var $string = "";

   function StringPrinter($string = "") {
      $this->string = $string;
   }

   function setString($string) {
      $this->string = $string;
   }

   function getString() {
      return $this->string;
   }

   function print() {
      echo $this->string;
   }

}

$sp = new StringPrinter();
$sp->setString("Hello World!");
$sp->print();
?>

How needlessly complicated can we make a "Hello World" script then? Anyone fancy doing a PHP-GTK one.

Rikki

Jul 10 2005, 12:20 PM

QUOTE(Wombat @ Jul 10 2005, 01:18 PM)

If you are going to use OOP at least make the class reusable, otherwise there's little point in bothering.

CODE

<?php

class StringPrinter {

   var $string = "";

   function StringPrinter($string = "") {
      $this->string = $string;
   }

   function setString($string) {
      $this->string = $string;
   }

   function getString() {
      return $this->string;
   }

   function print() {
      echo $this->string;
   }

}

$sp = new StringPrinter();
$sp->setString("Hello World!");
$sp->print();
?>

How needlessly complicated can we make a "Hello World" script then? Anyone fancy doing a PHP-GTK one.

Funny you should say that, I found a site that went from the easiest (echo "Hello World";) to the most complex which ran into a few hundred lines. I'll try and dig it up

[edit] http://www.ariel.com.au/jokes/The_Evolutio...Programmer.html

Brendon Koz

Jul 10 2005, 03:03 PM

QUOTE

http://www.ariel.com.au/jokes/The_Evolutio...Programmer.html

You're all GURU HACKERS!

AJHeat34

Jul 10 2005, 04:12 PM

can you do this in php?

<?php
$text="hello world!"
echo "$text";

notice the echo with no parantheses.

also when do you use print and echo? which one is better?

Dan C

Jul 10 2005, 04:48 PM

Whilst it will work, echo "$text"; is much less efficient than just echo $text;

As far as print and echo go, they are both essentially the same, so it doesn't really matter.

_

Jul 10 2005, 05:11 PM

echo is a tiny bit faster... I don't feel like explaining it, just search the web for 'echo vs print'.

bılʞ

Jul 10 2005, 05:36 PM

http://www.faqts.com/knowledge_base/view.phtml/aid/1/fid/40

giggsey

Jul 10 2005, 08:02 PM

QUOTE(AJHeat34 @ Jul 10 2005, 05:12 PM)

can you do this in php?

<?php
$text="hello world!"
echo "$text";

notice the echo with no parantheses.

also when do you use print and echo? which one is better?

That would give an error

Its trying to find ?>

FυsE

Jul 10 2005, 08:53 PM

Sorry for the mistakes, was really tired at the time

phatmonkey

Jul 11 2005, 08:57 AM

QUOTE(giggsey2 @ Jul 10 2005, 09:02 PM)

That would give an error

Its trying to find ?>

Missing end tags don't produce any errors as far as I know. I believe some people leave them out to prevent output at the end of classes and things.

Nash12

Jul 11 2005, 09:27 AM

QUOTE(Veracon @ Jul 10 2005, 07:11 PM)

echo is a tiny bit faster... I don't feel like explaining it, just search the web for 'echo vs print'.

Because print returns a value (1 or 0) whether the "printing" was successfull or not.

Frankl.in

Jul 11 2005, 10:34 PM

QUOTE(.Cole @ Jul 10 2005, 02:48 AM)

ahahah Lol, this wasnt designed for matt, this was designed to help people who are starting to learn PHP should know the basics

Can't you just let them read Getting Started or Your first PHP-enabled page at PHP.net instead of showing buggy code?

Perhaps you could start there yourself too.....

Anyway, when you define a class, don't you think it should be called somewhere in the code? Because auto_run() is an IPB-thing, but you didn't tell if it's included or required by another IPB script or any other script that calls auto_run() in the 'hello' class.

A hint:

CODE

$foo = new hello;
$foo->auto_run();

Did you actually try to run that class without calling it? If so, did it work? Or is this more meant to be a tutorial about bugfixing where your first post in this topic is the example code?

Gism0

Jul 15 2005, 08:56 PM

<?="Hello world!"?>

Dan C

Jul 16 2005, 10:36 AM

QUOTE(Gism0 @ Jul 15 2005, 09:56 PM)

<?="Hello world!"?>

That's not very portable

Mentor

Jul 16 2005, 04:47 PM

Hi,

whats about this:

index.php

CODE

<?php
require( "hello.php" );
$hello = new hello();
$hello->out();
?>

hello.php

CODE

<?php

class hello
{
    var $out    = "";

    function hello()
    {


    }

    function out()
    {
        $this->out = "Hello ";

        require( "world.php" );

        $world = new world();

        $world->say_world(&$this);

        echo $this->out;
    }
}

?>

world.php

CODE

<?php

class world extends hello
{
    function say_world($class)
    {

        $class->out .= " world";
    }
}

?>

Stephen

Jul 16 2005, 09:42 PM

Is this possibly the most pointless topic ever?

Dan C

Jul 16 2005, 09:49 PM

No, I could name a few more pointless ones...

Gism0

Jul 17 2005, 12:27 AM

QUOTE(Dan C @ Jul 16 2005, 11:36 AM)

That's not very portable

hehe it looks cool though