How can I explode and trim whitespace?

An improved answer

preg_split ('/(\s*,*\s*)*,+(\s*,*\s*)*/', 'red,     green thing ,,
              ,,   blue ,orange');

Result:

Array
(
    [0] => red
    [1] => green thing
    [2] => blue
    [3] => orange
)

This:

• Splits on commas only
• Trims white spaces from each item.
• Ignores empty items
• Does not split an item with internal spaces like "green thing"

You can do the following using array_map:

$new_arr = array_map('trim', explode(',', $str));