Issue3888 fix (#4016)

* Improper exception handling demonstration #3888
#3888

* Exception handling demonstration removed as unessesary

* Class name typo and comment formatting

* #3888 VB fix to match CS code

Author: jinek

samples/snippets/csharp/VS_Snippets_Wpf/ContentControlTemplateSelector/CSharp/Window1.xaml

@@ -24,7 +24,9 @@
       </Grid>
     </DataTemplate>
 
-    <local:NumderDataTemplateSelector x:Key="numberTemplateSelector"/>
+    <local:NumberDataTemplateSelector x:Key="numberTemplateSelector"
+                                      NumberTemplate="{StaticResource numberTemplate}"
+                                      LargeNumberTemplate="{StaticResource largeNumberTemplate}"/>
 
   </Window.Resources>
   <StackPanel>

samples/snippets/csharp/VS_Snippets_Wpf/ContentControlTemplateSelector/CSharp/Window1.xaml.cs

@@ -30,42 +30,29 @@ public Window1()
     }
 
     //<Snippet2>
-    public class NumderDataTemplateSelector : DataTemplateSelector
+    public class NumberDataTemplateSelector : DataTemplateSelector
     {
+        public DataTemplate NumberTemplate { get; set; }
+        public DataTemplate LargeNumberTemplate { get; set; }
+
         public override DataTemplate SelectTemplate(object item, DependencyObject container)
         {
-            string numberStr = item as string;
-
-            if (numberStr != null)
+            // Null value can be passed by IDE designer
+            if (item == null) return null;
+
+            var num = Convert.ToInt32((string)item);
+            
+            // Select one of the DataTemplate objects, based on the 
+            // value of the selected item in the ComboBox.
+            if (num < 5)
             {
-                int num;
-                Window win = Application.Current.MainWindow;
-
-                try
-                {
-                    num = Convert.ToInt32(numberStr);
-                }
-                catch
-                {
-                    return null;
-                }
-
-                // Select one of the DataTemplate objects, based on the 
-                // value of the selected item in the ComboBox.
-                if (num < 5)
-                {
-                    return win.FindResource("numberTemplate") as DataTemplate;
-                }
-                else
-                {
-                    return win.FindResource("largeNumberTemplate") as DataTemplate;
-
-                }
+                return NumberTemplate;
+            }
+            else
+            {
+                return LargeNumberTemplate;
             }
-
-            return null;
         }
-
     }
     //</Snippet2>
 }

samples/snippets/visualbasic/VS_Snippets_Wpf/ContentControlTemplateSelector/VisualBasic/Window1.xaml

@@ -24,7 +24,9 @@
       </Grid>
     </DataTemplate>
 
-    <local:NumderDataTemplateSelector x:Key="numberTemplateSelector"/>
+    <local:NumberDataTemplateSelector x:Key="numberTemplateSelector"
+                                      NumberTemplate="{StaticResource numberTemplate}"
+                                      LargeNumberTemplate="{StaticResource largeNumberTemplate}"/>
 
   </Window.Resources>
   <StackPanel>

samples/snippets/visualbasic/VS_Snippets_Wpf/ContentControlTemplateSelector/VisualBasic/Window1.xaml.vb

@@ -29,36 +29,31 @@ End Class 'Window1
 
 
 '<Snippet2>
-Public Class NumderDataTemplateSelector
+Public Class NumberDataTemplateSelector
     Inherits DataTemplateSelector
 
+    Public Property NumberTemplate As DataTemplate
+    Public Property LargeNumberTemplate As DataTemplate
+
     Public Overrides Function SelectTemplate(ByVal item As Object, _
                     ByVal container As DependencyObject) As DataTemplate
 
-        Dim numberStr As String = item '
-
-        If Not (numberStr Is Nothing) Then
-            Dim num As Integer
-            Dim win As Window = Application.Current.MainWindow
+        ' Nothing can be passed by IDE designer
+        if (item Is Nothing) Then
+            Return Nothing
+        End If
 
-            Try
-                num = Convert.ToInt32(numberStr)
-            Catch
-                Return Nothing
-            End Try
+        Dim num = Convert.ToInt32(CStr(item))
 
-            ' Select one of the DataTemplate objects, based on the 
-            ' value of the selected item in the ComboBox.
-            If num < 5 Then
-                Return win.FindResource("numberTemplate") '
+        ' Select one of the DataTemplate objects, based on the 
+        ' value of the selected item in the ComboBox.
+        If num < 5 Then
+            Return NumberTemplate
 
-            Else
-                Return win.FindResource("largeNumberTemplate") '
-            End If
+        Else
+            Return LargeNumberTemplate
         End If
 
-        Return Nothing
-
     End Function 'SelectTemplate
 End Class 'NumderDataTemplateSelector 
 '</Snippet2>