jquery compatible scroll event

FireFox browser uses DOMMouseScroll event, others (including IE6) use onmousewheel event;
wheelDelta in FireFox determines the scrolling direction, its value is 120/-120, when it is negative, it means scrolling down, and when it is an integer, scrolling up
Others: detail (Attribute) Judging the direction, the return value is an integer multiple of 3 (3/-3), a positive number means scrolling up, and a negative number scrolling down.
Opera: has both wheelDelta and detail, where the "detail" attribute returns the value and the one in FF. wheelDelta is the same

which is:

 1 // jquery 兼容的滚轮事件
 2     $(document).on("mousewheel DOMMouseScroll", function (e) {
 3         console.log(e);
 4         
 5         var delta = (e.originalEvent.wheelDelta && (e.originalEvent.wheelDelta > 0 ? 1 : -1)) ||  // chrome & ie
 6             (e.originalEvent.detail && (e.originalEvent.detail > 0 ? -1 : 1));              // firefox
 7         if (delta > 0) {
 8             // 向上滚
 9             console.log("wheelup");
10         } else if(delta < 0 ) {
 11              // roll down 
12              console.log("wheeldown" );
 13          }
 14      });