Javascript back to the top effect implementation code _ javascript tips-js tutorial

This article mainly introduces the implementation code of javascript back to the top. If you need it, you can refer to it and hope to help you. The Code is as follows:

// Speed rolling speed time Interval
Function gotoTop (speed, time ){

Speed = Rate | 0.1;
Time = time | 16;

// Horizontal distance from the scroll bar to the top of the page
Var x = document. body. scrollLeft;

// Vertical distance from the scroll bar to the top of the page
Var y = document. body. scrollTop;

// Rolling distance = current distance/speed, because the smaller the distance, the speed is greater than 1, so the rolling distance will be smaller and smaller
Speed ++;
Window. scrollTo (Math. floor (x/speed), Math. floor (y/speed ));

// If the distance is not zero, continue to call the iteration function.
If (x> 0 | y> 0 ){

Window. setTimeout ("gotoTop (" + speed + "," + time + ")", time );
}
}