How to verify with JavaScript if canvas is supported?

Question

The following HTML allows to inform users in case canvas element is not supported by browser:

<canvas id="canvas">
  Your browser doesn't support canvas element
</canvas>

How could I get the same information with JavaScript (for ex., to disable some button)?

Answer 1

You can try creating a canvas and check for a method:

var supportsCanvas = !!document.createElement("canvas").getContext;