小编Who*_*AmI的帖子

var canvas = document.getElementById("canvas");
var info = document.getElementById("info");

function getMovements(e) {
  info.innerHTML =  "x change: " + String(e.movementX) + " , y change: " + String(e.movementY);
}

canvas.addEventListener("mousemove", getMovements);

canvas {
  background-color:bisque;
}

<canvas id ="canvas" width=300, height=300></canvas>
<div id=info></div>