new folder structure and new C# script host

src/WPF/SearchTextBoxUserControl.xaml.cs

@@ -0,0 +1,48 @@
+
+using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Input;
+
+namespace Controls
+{
+    public partial class SearchTextBoxUserControl : UserControl
+    {
+        public SearchTextBoxUserControl()
+        {
+            InitializeComponent();
+        }
+
+        public string Text { get => SearchTextBox.Text; set => SearchTextBox.Text = value; }
+
+        string _HintText;
+
+        public string HintText {
+            get => _HintText;
+            set {
+                _HintText = value;
+                UpdateControls();
+            }
+        }
+
+        void SearchClearButton_Click(object sender, RoutedEventArgs e)
+        {
+            SearchTextBox.Text = "";
+            Keyboard.Focus(SearchTextBox);
+        }
+
+        void SearchTextBox_TextChanged(object sender, TextChangedEventArgs e)
+        {
+            UpdateControls();
+        }
+
+        void UpdateControls()
+        {
+            HintTextBlock.Text = SearchTextBox.Text == "" ? HintText : "";
+
+            if (SearchTextBox.Text == "")
+                SearchClearButton.Visibility = Visibility.Hidden;
+            else
+                SearchClearButton.Visibility = Visibility.Visible;
+        }
+    }
+}