javascript实现的白板效果(可以直接在网页上写字)

代码如下: [removed] var ball; var mouseX = 100; var mouseY = 100; var angle = 0; var radius = 0; function draw(){ ball = document.createElement(“span”); ball.style.position = “absolute”; ball.style.color = “#FF0000”; ball.style.zIndex = 999999999; ball[removed] = “●”; document.bod