Is this a good way of writing long conditions in PHP? - php

Question

I have to evaluate a very long condition in PHP, so, to avoid errors and trying to write more readable code, I did the following:
//this returns 1 when true, and nothing when false, although expected TRUE or FALSE
$isNameValid=strlen($dataDecoded['nombre'])>=3;
$isDescriptionValid=(strlen($dataDecoded['descripcion'])>=10) && strlen($dataDecoded['descripcion'])<=300;
$isPriceValid=$dataDecoded['precio'] >0;
$isImageValid=(($dataDecoded['imagen'] != "") && ($dataDecoded['imagen'] != NULL) );
And now, I can make the following:
if($isNameValid==1 && $isDescriptionValid==1 && $isPriceValid==1 && $isImageValid==1)
{
echo "ok";
}
else{
echo "no";
}
It seems to work fine, but maybe is a weird way of doing things. I wanted to avoid the following, which I find more confusing and easy to make a mistake
if(strlen($dataDecoded['nombre'])>=3 && ... && ...)
Is there a better way to do that? Is wrong what I did? Thanks

Answer 1

I don't care for creating extra variables here; this makes code difficult to maintain and unreusable. I'd recommend breaking your validation logic into easy-to-read, maintainable, reusable functions:
function valid($data) {
return validName($data['nombre']) &&
validDescription($data['descripcion']) &&
validPrice($data['precio']) &&
validImage($data['imagen']);
}
function validName($name) {
return strlen($name) >= 3;
}
function validDescription($desc) {
return strlen($desc) >= 10 && strlen($desc) <= 300;
}
function validPrice($price) {
return $price > 0;
}
function validImage($image) {
return $image !== "" && $image != NULL;
}
$dataDecoded = [
"nombre" => "foo",
"descripcion" => "foo bar foo bar",
"precio" => 15,
"imagen" => "foo.png"
];
// now your main code is beautiful:
echo (valid($dataDecoded) ? "ok" : "no") . "\n";

Answer 2

Yes, that is acceptable. However, your variables there are all boolean, so you don't even need the ==1.
if($isNameValid && $isDescriptionValid && $isPriceValid && $isImageValid)

Answer 3

It really depends on how you want to handle it.
Is switch an option or a viable one?
Is ternary if prettier or handy?
From what I see, I'm guessing you have a validation purpose and a operating incoming depending on the validation. Why not create a function or a class that handles your input and validates? And in there, you can have all the dirty code you'd want. On your logical code, you'd just have to do (e.g of a class)
$someClass = new SomeClass();
$someClass->validate($fields);
if ($someClass->isValidated()) ...
This way, you'd actually follow some standards whereas the purpose of it would be to work as a validator for (all of? depends on your needs) your data
E.g of ternary ifs
$isNameValid = count($dataDecoded['nombre'])>=3 ? true : false;
$isDescriptionValid = count($dataDecoded['descripcion']) >= 10 && count($dataDecoded['descripcion']) <= 300 ? true : false;
$isPriceValid = count($dataDecoded['precio']) > 0 ? true : false;
$isImageValid = empty($dataDecoded['imagen']) === false ? true : false;
if ($isNameValid && $isDescriptionValid && $isPriceValid && $isImageValid) ...