一、Input 类型: color
color 类型用在input字段主要用于选取颜色，如下所示：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>菜鸟教程(runoob.com)</title>
</head>
<body><form action="demo-form.php">选择你喜欢的颜色: <input type="color" name="favcolor"><br><input type="submit">
</form></body>
</html>二、c++定义：
third_party\blink\renderer\core\html\forms\color_input_type.h
third_party\blink\renderer\core\html\forms\color_input_type.cc
namespace blink {class ColorChooser;class ColorInputType final : public InputType,public KeyboardClickableInputTypeView,public ColorChooserClient {public:explicit ColorInputType(HTMLInputElement&);~ColorInputType() override;void Trace(Visitor*) const override;using InputType::GetElement;// ColorChooserClient implementation.void DidChooseColor(const Color&) override;void DidEndChooser() override;Element& OwnerElement() const override;gfx::Rect ElementRectRelativeToLocalRoot() const override;Color CurrentColor() override;bool ShouldShowSuggestions() const override;Vector<mojom::blink::ColorSuggestionPtr> Suggestions() const override;ColorChooserClient* GetColorChooserClient() override;bool TypeMismatchFor(const String&) const;private:InputTypeView* CreateView() override;ValueMode GetValueMode() const override;void ValueAttributeChanged() override;void CountUsage() override;bool SupportsRequired() const override;String SanitizeValue(const String&) const override;void CreateShadowSubtree() override;void DidSetValue(const String&, bool value_changed) override;void HandleDOMActivateEvent(Event&) override;ControlPart AutoAppearance() const override;void OpenPopupView() override;void ClosePopupView() override;bool HasOpenedPopup() const override;bool ShouldRespectListAttribute() override;void WarnIfValueIsInvalid(const String&) const override;void UpdateView() override;AXObject* PopupRootAXObject() override;Color ValueAsColor() const;HTMLElement* ShadowColorSwatch() const;Member<ColorChooser> chooser_;
};template <>
struct DowncastTraits<ColorInputType> {static bool AllowFrom(const InputType& type) {return type.IsColorInputType();}
};} // namespace blink