[PHP]How to make your script easier

[stefans]

Hello all,

So this is a tutorial about how you can make your script easier..
You can do this by using functions, so you don't have to type the whole code again and again and again =p
You can have functions that return something, or just functions that do something..

So here's an example for a function to get player data..

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function getPlayerData($userid, $row) {
$query = mysql_query("SELECT * FROM users WHERE id = '".$userid."'");
$row2 = mysql_fetch_assoc($query);
return $row2[$row];
}

So this will give you the the value of the row of that userid
So what i do is make a page functions.php and include it in my config.php
then you can use your function like that

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echo "Your name is ".getPlayerData($_SESSION['id'], 'username');

so you get the username from the id from your account

Ok, so here's an example how to set player data

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 function setPlayerData($userid, $row, $value) {
mysql_query("UPDATE users SET ".$row." = '".$value."' WHERE id = '".$userid."'");
}

So this will set the entered value of the entered row of the entered userid
I also include this in my functions.php page
Now i'm going to give you an example of using the 2 functions together

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$currentmoney = getPlayerData($_SESSION['id'], 'money');
$newmoney = $currentmoney - 10;
setPlayerData($_SESSION['id'], 'money', $newmoney);

I just typed these here, so there can be some faults, but it's just to explain it all,
I did my best to explain it so =p

[Ark]

Awesome functions! Definately gonna use them! Thanks Stefans

[hallsofvallhalla]

Not sure I can recommend this. Player data should only be run once on a page. I would not rerun the function everytime i needed the data. Maybe I am not reading this correctly but it seems overkill.

If you pull the player data in the beginning of the page as i do in my tutorials $playerinfo3 stores all teh data for the rest of the script.

However if you are using javascript and ajax a script like this would be useful to pull updated data.

[Jackolantern]

I think he just means using the function to get the player data at the start of the script; not using it every time you need any info about the player. Because that definitely would be overkill and would tax the database for no reason.

Functions definitely are the backbone of procedural programming, and are very important. You could work in data-scrubbing algorithms into those functions so you can clean everything heading towards MySQL. Although the majority of the calls you make to the function will not have player-generated data that could be dangerous, sometimes it is best to assume you screwed up somewhere when it comes to stuff like this and just scrub everything provided your security algorithms are not too CPU-costly (and in PHP, they usually aren't).

[Ark]

Well yeah maybe not to get data but instead to delete it.

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function deleteData($table, $id)
{
    mysql_query("DELETE from ".$table." where id=".$id."");
}
 

It's more neat and simple.

[Jackolantern]

There is also the benefit of making your scripts cleaner and more maintainable by using functions. What their use does is separates out the implementation of functionality from the actual game logic. When the two are muddled together, it makes pages much harder to read, understand and update later.