Canvas record

1、 Filling and tracing api

context.strokeStyle = "red" // line color 
context.fillStyle = "red" // fill 
context.moveTo(100,100) // Start coordinates 
context.lineTo(200,200) // Coordinates of the end 
context.binginPath() // When drawing many kinds of figures 
context.clodePath()
context.stroke()
context.clearRect(x,y,width,hright) // Refresh the current palette 
context.fill()

2、 Draw arc

context.arc(10,10,5,0,2*Math.PI) // Origin coordinates , radius , from 0 Start , To 2π end （ Clockwise ）