Question

I try to delete more then one white characters from my string:

$content = preg_replace('/\s+/', " ", $content); //in some cases it doesn't work

but when i wrote

$content = preg_replace('/\s\s+/', " ", $content); //works fine

could somebody explain why?

because when i write /\s+/ it must match all with one or more white character, why it doesn’t work?

Thanks

Answer 1

What is the minimum number of whitespace characters you want to match?

\s+ is equivalent to \s\s* — one mandatory whitespace character followed by any number more of them.

\s\s+ is equivalent to \s\s\s* — two mandatory whitespace characters followed by any number more (if this is what you want, it might be clearer as \s{2,}).

Also note that $content = preg_replace('/\s+/', " ", $content); will replace any single spaces in $content with a single space. In other words, if your string only contains single spaces, the result will be no change.