javascript - Why and (&) in if statement is not working? -

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• javascript multiple keys pressed @ once 8 answers

so making html5 game working in movement. player can move w, a, s ,d in key. working wanted add power ..like if player press + space-bar or d + space-bar ability trigger.

i used , operator , should have worked in theory it's not working. new in html5 , appreciated. in advance.

here code... copy paste on html note.

<canvas id="canvas" width="800" height="500" style="border:1px solid #000000;"></canvas>  <script>     var c = document.getelementbyid("canvas").getcontext("2d");       var width = 800;     var height = 500;       var player = {         x: math.random() * width,         y: math.random() * height,         width: 30,         height: 30,         color: 'black',          pressingdown: false,         pressingup: false,         pressingleft: false,         pressingright: false,           pressinpowerright: false,         pressinpowerleft: false,     };        drawentity = function(e) {         c.fillstyle = e.color;         c.fillrect(e.x - e.width / 2, e.y - e.height / 2, e.width, e.height);     }       document.onkeydown = function(event) {         if (event.keycode === 68) //d             player.pressingright = true;         else if (event.keycode === 83) //s             player.pressingdown = true;         else if (event.keycode === 65) //a             player.pressingleft = true;         else if (event.keycode === 87) // w             player.pressingup = true;           else if (event.keycode === 68 && event.keycode === 32) // statement not working             player.pressinpowerright = true;         else if (event.keycode === 65 && event.keycode === 32) // statement not working              player.pressinpowerleft = true;      }      document.onkeyup = function(event) {         if (event.keycode === 68) //d             player.pressingright = false;         else if (event.keycode === 83) //s             player.pressingdown = false;         else if (event.keycode === 65) //a             player.pressingleft = false;         else if (event.keycode === 87) // w             player.pressingup = false;          else if (event.keycode === 68 && event.keycode === 32) // not working             player.pressinpowerright = false;         else if (event.keycode === 65 && event.keycode === 32) // not working             player.pressinpowerleft = false;     }      updateplayerposition = function() {         if (player.pressingright)             player.x += 5;         if (player.pressingleft)             player.x -= 5;         if (player.pressingdown)             player.y += 5;         if (player.pressingup)             player.y -= 5;          if (player.pressingpowerright)             player.x += 50;         if (player.pressingpowerleft)             player.x -= 50;     }      update = function() {         c.clearrect(0, 0, width, height);          updateplayerposition();         drawentity(player);      }      setinterval(update, 40); </script> 

by making if , else if tree making condition satisfied not further button presses. need check both button presses (space bar , a) before checking single button presses not short circuit logic