jquery: if (target) is child of ('.wrapper') then (do something)

.has() is maybe the mose convenient syntax:

if( $('.wrapper').has($(target)) ) {
     // do something
}

Even more 'powerful' (in terms of performance) is $.contains(). So an ideal algorithm should look like:

var $wrapper =  $('.wrapper'),
    $target  =  $(this).attr('href');

if( $.contains($wrapper[0], $target[0]) ) {
    // do something
}

Reference: .has(), $.contains()

if($(target).parents('.wrapper').length > 0) {
   //do something...
}

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