public void TestGetContentByExtension()
        {
            CopyrightCore.Load();
            var txt = CopyrightCore.GetContentByExtension(".cs");

            Assert.IsNotNull(txt);
        }
        /// <summary>
        /// This function is the callback used to execute the command when the menu item is clicked.
        /// See the constructor to see how the menu item is associated with this function using
        /// OleMenuCommandService service and MenuCommand class.
        /// </summary>
        /// <param name="sender">Event sender.</param>
        /// <param name="e">Event args.</param>
        private void MenuItemCallback(object sender, EventArgs e)
        {
            //获取服务,这玩意儿……可以理解为vs的服务对象吧。
            var dte       = this.ServiceProvider.GetService(typeof(DTE)) as DTE;
            var selection = dte.ActiveDocument.Selection as TextSelection;

            if (selection == null)
            {
                return;
            }
            //获取拓展名
            var ext = Path.GetExtension(dte.ActiveDocument.FullName);

            //删除所选内容
            if (!selection.IsEmpty)
            {
                selection.Delete();
            }

            var txt = CopyrightCore.GetContentByExtension(ext);

            if (txt == null)
            {
                return;
            }
            //Insert to top
            if (CopyrightCore.CurrentStoreConfig.IsInsertToTop)
            {
                selection.StartOfDocument();
            }
            selection.Insert(txt);

            //selection.Insert("//Demo test~~~" + Environment.NewLine + "//Test line 2");
        }