Array vs. parameters

[RobbiK]

Hi,
I'm starting to design a class which I will write in PHP, of course. What I'm wondering are what kind of paramaters to use in some functions.

Let's say I have a function that saves a user in a database and the table contains the fields Name, Password, email.

Now, as I see it there are two ways to do this. One is:

function InsertUser($Name,$Password,$email)

And another one is to use an array which contains these fields, i.e.

function InsertUser($Data)

Then I could retreive the name with Data['Name'], etc.

What I'm wondering is the pros of cons of using a number of parameter versus an array. In the above example this is maybe not a major issue, but what if I want to call a function that saves to a table that contains 15 fields. Then using 15 parameters would be rather silly 😉

Are there any obvious reasons not to use array as parameter for those kinds of functions??

[goa103]

Hello,

This is a pretty wise question ! The answer depends of the context. Is the number of parameters variable ? Can you easily provide an array ?...

paramaters :
Pros : you know what the parameters are, pretty cool to document your code using JavaDoc comments or simply to understand it, you can read the function name and the parameter names to understand what it does and how it works
Pros : faster code execution, you don't have to carry an array (but it won't put your server on its knees)
Cons : if you need to insert a user defined by 3 fields on Monday, 5 fields on Tuesday and 15 fields on Friday... you will have to update your parameter list 🙂. Anyway you still have to implement the insert behaviour... see next

arrays :
Pros : very useful for a generic method that will add something in your DB, the matter what the parameters are, if you insert algorithm is right, you don't have to change anything
Cons : if you don't well document your code the function prototype can confused other developers, what the hell is that $data thing ? isn't my user defined by its name, password and email ?
Cons : you carry an array... no big deal. You can still use a reference so the array is not copied.

So it depends of what you want. The idea is to plan what you want to do. What are the properties that define a user ? In theo ne hand you can create your InsertUser without worrying about new properties... Adding 1 or 2 parameters is not a big deal.

In the other hand you could create a generic function, with an array to handle future improvements : first name, last name, address...

IMHO if you want to control everything, don't use arrays, unless you really need a generic function that will handle ALL your inserts : users... It depends of what your application does. It's useful for a "InsertField" function, not a "InsertUser" function. Because here you know what you're doing, you know the parameters, what defines a user...

Creating a generic function for your whole application would mean to design a framework... So stick to the good old basics and everything should work fine.

JM. Molina

[RedDragon]

In your case i would suggest you to use an array...

Just imagine you would be extending your members table so your users can enter more details about themselves...

Then you will have to change (extend) the function to make it work... if you use an array you dont... -> php the dynamic language

goa103 you can believe me that the is no big difference in speed ... 20 entries vs. 1 array... i would suggest that the array is quite faster...

[goa103]

goa103 you can believe me that the is no big difference in speed ... 20 entries vs. 1 array... i would suggest that the array is quite faster... [/B]

As long as he uses a reference, using arrays won't slow down its script :

Cons : you carry an array... no big deal. You can still use a reference so the array is not copied.

Just imagine you would be extending your members table so your users can enter more details about themselves...

I forgot to mention that it also depends of where the data come from. I adviced him to use variables because inserting a user means someone filled in a form. Which means the $POST array is filled with the form data. So he doesn't have to do anything. He can directly use the $POST array in its InsertUser.

So RobbiK please let's us know more about the context, where does the data come from ?

JM. Molina