touch事件总结

$("body").on("touchstart", function(e) {

    e.preventDefault();

    startX = e.originalEvent.changedTouches[0].pageX,

    startY = e.originalEvent.changedTouches[0].pageY;

});

$("body").on("touchmove", function(e) {

    e.preventDefault();

    moveEndX = e.originalEvent.changedTouches[0].pageX,

    moveEndY = e.originalEvent.changedTouches[0].pageY,

    X = moveEndX - startX,

    Y = moveEndY - startY;

    if
( X > 0 ) {

        alert("left 2 right");

    }

    else
if  ( X < 0 ) {

        alert("right 2 left");

    }

    else
if  ( Y > 0) {

        alert("top 2 bottom");

    }

    else
if  ( Y < 0 ) {

        alert("bottom 2 top");

    }

    else{

        alert("just touch");

    }

});