how to detect a section is visible in jquery

1.is(':visible')
2//Selects all elements that are visible.
3
4if($('#yourDiv').is(':visible')){
5	//do stuff in here
6}
7//or
8$('#yourDiv:visible').callYourFunction();

1.is(':visible')
2//Selects all elements that are visible.
3
4if($('#Div').is(':visible')){
5	// add whatever code you want to run here.
6}
7
8$('#yourDiv:visible').callYourFunction();

1$('.eipC:visible').length 
2
3//or
4
5$('.eipC').is(':visible').length
6

1$.fn.isInViewport = function() {var elementTop = $(this).offset().top;var elementBottom = elementTop + $(this).outerHeight();var viewportTop = $(window).scrollTop();var viewportBottom = viewportTop + $(window).height();return elementBottom > viewportTop && elementTop < viewportBottom;};