如何将自定义字符串替换为正则表达式区域

Question

I'm building "get all site links" class lib in my application. Function parameters are segments and returning as website url.

My regexs that stored in database like that blog/([az]+)(/[a-z0-9.-]+)?

I want to replace regexs with my "matched" data (segments).

Segments are string or array, may be both. But prefered using as array

Example 1:

Regex : blog/([az]+)(/[a-z0-9.-]+)?

Segments : news , new-software-released

Result : blog/news/new-software-released

Example 2:

Regex : blog/([az]+)(/[a-z0-9.-]+)?

Segments : news

Result : blog/news

Example 3:

Regex : user(/[a-z0-9.-]+)?

Segments : johndoe

Result : user/johndoe

Tried preg_replace array but i couldnt figure out:

function get_url($segments){
    $regex = "blog/([a-z]+)(/[a-z0-9.-]+)?"
    $replacements = explode('|', trim($segments));
    $count = 0;
    return preg_replace('/'.$regex.'/', '$replacements[$count++]', $regex);
}

echo get_url('news|new-software-released');

Answer 1

I still don't really understand what you're doing, but it seems like this would do what you're after:

function get_url($prefix, $segments) {
    return $prefix . '/' . implode('/', explode('|', $segments));
}

echo get_url('blog', 'news|new-software-released');
echo get_url('blog', 'news');
echo get_url('user', 'johndoe');

Answer 2

It work well:

<?PHP
function get_url($segments){
    $regex = "blog/([a-z]+)(/[a-z0-9.-]+)?";
    $url = "blog/test";
    $replacements = explode('|', trim($segments));
    if(count($replacements) > 1) $replacements = 'blog/' . $replacements[0] . '/' . $replacements[1];
    else $replacements = 'blog/' . $replacements[0];
    $count = 0;
    return preg_replace('#'.$regex.'#', $replacements, $url);
}

echo get_url('news|new-software-released');

Thats return value is blog/news/new-software-released