Check if class exists somewhere in parent - vanilla JS

Question

I\'m really struggling to see how to do this. I want to check if a class exsits somewhere in one of the parent elements of an element.

I don\'t want to use any libra

Answer 1

I'm ok with the function that Denys Séguret posted, it looks elegant and I like it. I just tweaked a little bit that function since if the class specified in the parameter, is not present in the whole DOM, it fails when the recursion reaches the document object because is true that we control if the element has the parent node (in the last line, and when the document is the element the parent node is null) but before we execute the previous line, and when the element is the document, document.className is undefined and it fails, so the control must be moved to the top.

function hasSomeParentTheClass(element, classname) {
    //
    // If we are here we didn't find the searched class in any parents node
    //
    if (!element.parentNode) return false;
    //
    // If the current node has the class return true, otherwise we will search
    // it in the parent node
    //
    if (element.className.split(' ').indexOf(classname)>=0) return true;
    return hasSomeParentTheClass(element.parentNode, classname);
}