$_POST vs $_GET

[Trium918]

I have created 30 pages and counting without using

a single $_GET variable. I guess you can say that I really

donnot have an understanding of how to use and when to

use the $_GET variable. Which is true because http://php.net

doesn't help; therefore, I am asking for one of you to go into

more detail then what other websites have to offer. Thanks!'

 

Some you are probably wondering the same thing, I hope. 

 

[Wildbug]

From:  http://us.php.net/manual/en/reserved.variables.php#reserved.variables.get

 

"An associative array of variables passed to the current script via the HTTP GET method. Automatically global in any scope."

 

Those are variables passed by URLs such as http://whatever.com/script.php?this=that&id=2, otherwise known as the HTTP GET method (as opposed to POST).

 

Thus, within script.php, $_GET['this'] = "that" and $_GET['id'] = 2.

[pocobueno1388]

The $_GET method works with the URL instead of post data.

 

Lets take this URL for example:

www.example.com/index.php?user=Trium918

 

This could be useful if you had a profile for your users and you got whos profile to display from the URL. You  would get the persons name with the $_GET method like so:

<?php
$user = $_GET['user'];
echo $user; //will print "Trium918"
?>

 

You could now use this username from the URL to pull information on the user from the database.

 

<?php

$user = $_GET['user'];

$sql = mysql_query("SELECT name, address, country, age FROM users WHERE username='" . $user . "'");

if (mysql_num_rows($sql) > 0)){
  //print all the users information here
} else {
   echo "No such user";
}

?>

 

That is just one example out of many...hopefully that clears it up a bit.

[marf]

$_GET i find I use only when making pages with search queries, because it doesn't matter if the user can see that in the top browser bar. Also makes clicking the 'back'' button more friendly instead of that message when using POST pops up.

[pocobueno1388]

@marf - Thats why you put this bit of code at the top of your scripts:

header("Cache-control: private");

[per1os]

@marf - Thats why you put this bit of code at the top of your scripts:

header("Cache-control: private");

 

If that is true (which I will be testing when I get home) you could of saved me headaches years ago with this stupid post problem. I will be running tests later tonight on it.

[pocobueno1388]

Did the trick for any website I have used it on =]

[Trium918]

Thanks to all! I have another question.

Is it possible to write an entire website without

the use of $_GET?

 

What does the code below prevents?

<?php
header("Cache-control: private");
?>

[Wildbug]

It's possible to write an entire website without PHP.  Likewise, there are plenty of PHP features it's possible not to use, including GET methods.

[pocobueno1388]

Cache-control: private

Indicates that all or part of the response message is intended for a single user and MUST NOT be cached by a shared cache. This allows an origin server to state that the specified parts of the response are intended for only one user and are not a valid response for requests by other users. A private (non-shared) cache MAY cache the response.

 

Note: This usage of the word private only controls where the response may be cached, and cannot ensure the privacy of the message content.

 

Whatever that means...haha. I basically use it so that when you click back on your browser after submitting post data it doesn't give you a popup telling you about it then forces you to refresh the page and resubmit everything.