Wordpress ajax call

I have a small question for you. How can I dinamicaly get a plugin file path? I want to make an ajax call from a page to a file wich is in my plugins direct开发者_开发问答ory, and I don't want to use wp-content/ . . . . etc Is there a way to do that? So it can work on every site. Thank you

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is this what you looking for:

$plugin_url =WP_PLUGIN_URL.'/'.dirname(plugin_basename (__FILE__));

this must be placed in your plugin file.