php file renaming loop

Question

I run a ecommerce site, and I have tons of product images. The naming rules are simple: productid-picnumber.

But sometimes theres gaps betweeen the picnumbers.

Example for the pictures for product id 4519:

4519-0.jpg
4519-3.jpg
4519-4.jpg
4519-5.jpg
4519-8.jpg

I'm trying to write an algorithm to rename the pictures. The pictures from this product should be renamed like this:

4519-0.jpg
4519-1.jpg
4519-2.jpg
4519-3.jpg
4519-4.jpg

In order. 0 must always be 0, as it's the main product image. -0 is always there. Let's say $ids is an array containing all my product ids.

Is looping through the product ids and using file_exists() the best way?

I mean, is there a fundamental reason that the `-#` needs to be sequential? — Jared Farrish, Oct 10 '11 at 23:30
the reason is the function for printing my product images goes like this. it loops, and checks if -1 exists, if it does, it prints it, and then it checks -2 and prints, and so on — Kristian Rafteseth, Oct 10 '11 at 23:32
This might be useful: http://stackoverflow.com/questions/2562298/php-how-to-search-a-file-using-wildcards — Jared Farrish, Oct 10 '11 at 23:35
thank you, i didnt know glob could do wildcards. i rather changed my file read function — Kristian Rafteseth, Oct 10 '11 at 23:59
My own preference would be to ignore the blanks in the sequence, unless I just have to have the numbers in order for some reason. — Jared Farrish, Oct 11 '11 at 00:02

score 3 · Accepted Answer · answered Oct 10 '11 at 23:23

I highly suggest you that you get all filenames from a directory listing first, and then run the renaming "dry" (map oldname -> new name for the files to change) and then output if the actual result of the operation is the expected result.

This will not only save you much file_exists checks but also keeps things more safely.

Additionally you can think of using some standard file-system utilities which can rename/renumber files quite quickly. Check your OS documentation.

php file renaming loop

1 Answers1