function srcoll(index,timer,speed) {
    var number=document.body.scrollTop-(lin_setFullHeight()*(index-1))
    console.log('number',number)
    if(number>0){
        document.body.scrollTop-=speed
        window.requestAnimationFrame(function () {
            srcoll(index,timer,speed)
        });
    }
    if(number==0){
        console.log("stop scrollling")
        window.cancelAnimationFrame(timer)
    }
    if(number<0){
        document.body.scrollTop+=speed
        window.requestAnimationFrame(function () {
            srcoll(index,timer,speed)
        });
    }
}

因为950-7-7这样减下去怎么样都不会等于0吧 为什么还是停下来了
那个lin_setFullHeight()是950