url参数替换的正则表达式

Question

I've done little with Regex, but I know this has to be simpler than I'm making it.

Given a URL that looks like this:

/p1/p2/{p3}/{p4}/.../{pn}

where {p3}, {p4} contain keys to an associate array.

I want to replace the values in the braces with the value in the braces (more specifically, a value in an associative array where this is the key)

So this ultimately becomes

/p1/p2/p3/p4 and ultimately /p1/p2/v3/v4

I suppose I could just replace the '{}' with empty, but I want the replacement string to match the contents of the original expression exactly so the lookup in the array works.

I'm using the PHP function preg_replace.

/(\w+)/({\w+})/ doesn't quite work...

Answer 1

While I'm not sure if I parsed your question right, this might a possible solution:

$pattern = "/p1/p2/{p4}/{p5}/foo/bar/baz";
$values = array(
    'p4' => 'eggs',
    'p5' => 'spam',
);

$pattern_fixed = preg_replace_callback("#{(.*?)}#", function ($match) use ($values) {
    return isset($values[$match[1]]) ? $values[$match[1]] : $match[1];
}, $pattern);

var_dump($pattern_fixed);

Output:

string(28) "/p1/p2/eggs/spam/foo/bar/baz"