JS to determine the direction of the element slide (up or down) mobile end

learn a little bit every day.

1 varstartx, Starty;2     //Get Angle3     functionGetangle (ANGX, angy) {4         returnMath.atan2 (Angy, ANGX) * 180/Math.PI;5     };6  7     //return direction 1 up 2 down 3 Left 4 right 0 not sliding according to the starting point8     functiongetdirection (StartX, Starty, EndX, Endy) {9         varANGX = EndX-StartX;Ten         varAngy = Endy-Starty; One         varresult = 0; A   -         //if the sliding distance is too short -         if(Math.Abs (ANGX) < 2 && Math.Abs (angy) < 2) { the             returnresult; -         } -   -         varAngle =Getangle (ANGX, angy); +         if(Angle >= -135 && angle <=-45) { -result = 1; +}Else if(Angle > && Angle < 135) { Aresult = 2; at}Else if((angle >= 135 && Angle <= 180) | | (Angle >= -180 && Angle <-135)) { -result = 3; -}Else if(Angle >= -45 && Angle <= 45) { -result = 4; -         } -   in         returnresult; -     } to     //Finger touch Screen +Document.addeventlistener ("Touchstart",function(e) { -StartX = E.touches[0].pagex; theStarty = E.touches[0].pagey; *},false); $     //finger off the screenPanax NotoginsengDocument.addeventlistener ("Touchend",function(e) { -         varEndX, Endy; theEndX = E.changedtouches[0].pagex; +Endy = E.changedtouches[0].pagey; A         varDirection =getdirection (StartX, Starty, EndX, Endy); the         Switch(direction) { +              Case0: -Alert ("Not sliding! "); $                  Break; $              Case1: -Alert ("Up! ") -                  Break; the              Case2: -Alert ("Down! ")Wuyi                  Break; the              Case3: -Alert ("Left! ") Wu                  Break; -              Case4: AboutAlert ("Right! ") $                  Break; -             default: -         } -},false);

Original address: http://www.cnblogs.com/beiz/p/5817192.html

JS to determine the direction of the element slide (up or down) mobile end