Answer by Mats for Prevent BODY from scrolling when a modal is opened

If modal are 100% height/width "mouseenter/leave" will work to easily enable/disable scrolling. This really worked out for me:

var currentScroll=0;
function lockscroll(){
    $(window).scrollTop(currentScroll);
} 
$("#myModal").mouseenter(function(){
    currentScroll=$(window).scrollTop();
    $(window).bind('scroll',lockscroll); 
}).mouseleave(function(){
    currentScroll=$(window).scrollTop();
    $(window).unbind('scroll',lockscroll); 
});