implement enum for types, implement OpenDialog from Dialog-API

ElectronNET.API/Entities/ThumbarButtonFlag.cs

@@ -0,0 +1,35 @@
+namespace ElectronNET.API.Entities
+{
+    public enum ThumbarButtonFlag
+    {
+        /// <summary>
+        /// The button is active and available to the user.
+        /// </summary>
+        enabled,
+
+        /// <summary>
+        /// The button is disabled.It is present, but has a visual state indicating it will not respond to user action.
+        /// </summary>
+        disabled,
+
+        /// <summary>
+        /// When the button is clicked, the thumbnail window closes immediately.
+        /// </summary>
+        dismissonclick,
+
+        /// <summary>
+        /// Do not draw a button border, use only the image.
+        /// </summary>
+        nobackground,
+
+        /// <summary>
+        /// The button is not shown to the user.
+        /// </summary>
+        hidden,
+
+        /// <summary>
+        /// The button is enabled but not interactive; no pressed button state is drawn.This value is intended for instances where the button is used in a notification.
+        /// </summary>
+        noninteractive
+    }
+}