CANVAS 要素

interface HTMLCanvasElement : HTMLElement {
           attribute unsigned long width;
           attribute unsigned long height;

  DOMString toDataURL(optional DOMString type, any... arguments);
  DOMString toDataURLHD(optional DOMString type, any... arguments);
  void toBlob(FileCallback? _callback, optional DOMString type, any... arguments);
  void toBlobHD(FileCallback? _callback, optional DOMString type, any... arguments);

  object? getContext(DOMString contextId, any... arguments);
  boolean supportsContext(DOMString contextId, any... arguments);
};