Setting a variable in a for loop...

therealchuckles

Sorry, I searched around and couldn't find anything to answer my specific question.

I am making this page for a pretend library, where people can check out books. They can check out any amount, they enter the amount, then enter the names.

So, I wanted to update a database, saying that the books were 'signed out'. This is where my question comes in.

Say a user takes out 3 books. I have three parameters in the url, book1, book2, book3, each containing the name of the book. I also have parameter called numBooks that tells how many books they want to take out

The code I tried looked something like this:

$num = $_GET['numBooks'];
for($i=1;$i<=$num;$i++) {
$book{$i} = $_GET["book{$i}"];
}

That didn't work. Is there a way to do it? If so, how?

tekky

for($i=0;$i<$numbooks;$i++)
{
     echo $book[$i]. " is checked out!<br>";
}

this would loop through $book[] and print out the values of $book[0] $book[1] $book[2].. till you got to $book[$numbook-1]

therealchuckles

Ok, that helps, but I don't have the $book[] set yet.

I need a way to get an undetermined amount of parameters into variables.

I need the book1 parameter into the $book1 variable, book2 into $book2, etc...

I could set it so that they can only check out a maximum of 5 books, calling book1, book2, book3, etc, but that would be kind of limiting.

tekky

how are you passing the variables to this page?

therealchuckles

If the user wanted to check out three books, the URL looks like this:

http://domain.com/script.php?numBooks=3&book1=Name1&book2=Name2&book3=Name3

It would be longer if the user checked out 50 books, of course.

Not sure if that's what you meant, but that's what I understood it to mean.

tekky

oke and you want them accessible via $book1/2/3 etc?

for that... you can use this

while(list($key, $val) = each($_GET)) { $$key =$val; }
echo "$book1, $book2, $book3";

this would print out
title1, title2, title3

and ANY variable passed int he URL like &babys=bad&kids=worse&women=sqrt(evil)

would be accessible by $babys $kids $women and set to bad worse sqrt(evil) respectively

therealchuckles

Ok, while that scripts not what I expected, it works.

I'll just write some extra code to check to see if the variables empty, then just stop there. Thanks for your help!

tekky

sure you can do this...

$books=0;
while(list($key, $val) = each($_GET))
{
     $$key =$val;
     if (strncmp($key, 'book', 4) == 0) { $books++; }
}
for ($i=1;$i=<$books;$i++)
{
     $temp = 'book' .$i;
     $temp = {${$temp}};
     $str .= "$temp ";
}
echo "$books books were ordered: $str";

I think that will work for what you neeed...

tekky

bah, after all that 😉

o-well glad you got something you can work with now 😃

therealchuckles

Lol, I decided to give your previous script a try, except now I'm getting this error:

Parse error: parse error, unexpected '{' in /var/www/html/library/sign_out.php on line 44

Which happens to be this line: $temp = {${$temp}};

EDIT: Again, never mind, I'm going to take a different road with this. Thanks again for the help.

tekky

yah I expected that would error... figured I would try it none the less

working on an image script myself, so was hurrying through that :/ sorry couldnt help you more 🙂

therealchuckles

Yeah, it's not a problem. I figured out a better way of doing things. Thanks again!