Updated the tool to inspect a whole string instead of a mere character.

2014-10-25 01:15:03 +02:00
parent e1f5c1c471
commit 6af77ad909
3 changed files with 201 additions and 16 deletions
@@ -0,0 +1,187 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Collections.Specialized;
+using System.Globalization;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace UnicodeCharacterInspector
+{
+	internal sealed class CharacterInspectorViewModel : BindableObject
+	{
+		private class CharacterCollection : INotifyCollectionChanged, IList<string>
+		{
+			public event NotifyCollectionChangedEventHandler CollectionChanged
+			{
+				add { owner.CollectionChanged += value; }
+				remove { owner.CollectionChanged -= value; }
+			}
+
+			private CharacterInspectorViewModel owner;
+
+			internal CharacterCollection(CharacterInspectorViewModel owner)
+			{
+				this.owner = owner;
+			}
+
+			public string this[int index]
+			{
+				get
+				{
+					if (index < 0 || index >= owner.characterCount) throw new IndexOutOfRangeException();
+
+					return owner.characters[index];
+				}
+			}
+
+			string IList<string>.this[int index]
+			{
+				get { return this[index]; }
+				set { throw new NotSupportedException(); }
+			}
+
+			public int Count { get { return owner.characterCount; } }
+
+			bool ICollection<string>.IsReadOnly { get { return true; } }
+
+			void ICollection<string>.Add(string item) { throw new NotSupportedException(); }
+			void IList<string>.Insert(int index, string item) { throw new NotSupportedException(); }
+
+			bool ICollection<string>.Remove(string item) { throw new NotSupportedException(); }
+			void IList<string>.RemoveAt(int index) { throw new NotSupportedException(); }
+
+			void ICollection<string>.Clear() { throw new NotSupportedException(); }
+
+			public int IndexOf(string item) { return Array.IndexOf(owner.characters, item); }
+			public bool Contains(string item) { return Array.IndexOf(owner.characters, item) >= 0; }
+
+			public void CopyTo(string[] array, int arrayIndex) { owner.characters.CopyTo(array, arrayIndex); }
+
+			public IEnumerator<string> GetEnumerator()
+			{
+				int length = owner.characterCount;
+				var array = owner.characters;
+
+				for (int i = 0; i < length; ++i)
+					yield return array[i];
+			}
+
+			IEnumerator IEnumerable.GetEnumerator() { return GetEnumerator(); }
+		}
+
+		private event NotifyCollectionChangedEventHandler CollectionChanged;
+
+		private string text;
+		private int selectedCharacterIndex = -1;
+		private string[] characters = new string[1024];
+		private int characterCount;
+		private CharacterInfoViewModel selectedCharacterInfo = new CharacterInfoViewModel();
+		private readonly CharacterCollection characterCollection;
+
+		public CharacterInspectorViewModel()
+		{
+			characterCollection = new CharacterCollection(this);
+        }
+
+		private void NotifyCollectionChanged(NotifyCollectionChangedAction action)
+		{
+			var handler = CollectionChanged;
+
+			if (handler != null)
+				handler(this, new NotifyCollectionChangedEventArgs(action));
+		}
+
+		public string Text
+		{
+			get { return text; }
+			set
+			{
+				// Analyze the string to detect if there are any similarities between the new and old values.
+				bool keepSelectedIndex = value != null
+					&& text != null
+					&&
+					(
+						value.Length <= text.Length ?
+							text.StartsWith(value, StringComparison.Ordinal) :
+							value.StartsWith(text, StringComparison.Ordinal)
+					);
+
+				// Here, we can deduce the information on string equality and simply return if needed.
+				if (keepSelectedIndex && value.Length == text.Length) return;
+
+				// We don't need the old value anymore.
+				text = value;
+
+				// We always need to reparse the text, as it is not possible to directly map between UTF-16 elements and their respective code point indexes.
+				int index = 0;
+				if (!string.IsNullOrEmpty(value))
+				{
+					var enumerator = StringInfo.GetTextElementEnumerator(value);
+
+					while (enumerator.MoveNext())
+					{
+						if (index >= characters.Length) Array.Resize(ref characters, characters.Length * 2);
+
+						// We don't replace pre-existing elements if they already have the correct value.
+						// This should help a bit with GC, by making new string elements as short-lived as possible.
+						string element = enumerator.GetTextElement();
+						if (characters[index] != element) characters[index] = element;
+
+						++index;
+					}
+				}
+				characterCount = index;
+
+				// Now that we parsed the text, we really know whether the previous selected index should be left untouched.
+				if (!(keepSelectedIndex = keepSelectedIndex && selectedCharacterIndex < characterCount || selectedCharacterIndex == -1)) selectedCharacterIndex = -1;
+
+				// After all this, raise the change notifications as needed. 😊
+				NotifyPropertyChanged();
+				NotifyCollectionChanged(NotifyCollectionChangedAction.Reset);
+				if (!keepSelectedIndex)
+				{
+					NotifyPropertyChanged("SelectedCharacterIndex");
+					NotifyPropertyChanged("SelectedCharacter");
+					selectedCharacterInfo.Character = null;
+				}
+            }
+		}
+
+		public ICollection<string> Characters { get { return characterCollection; } }
+
+		public int SelectedCharacterIndex
+		{
+			get { return selectedCharacterIndex; }
+			set
+			{
+				if (selectedCharacterIndex < -1 || selectedCharacterIndex >= characters.Length)
+					throw new ArgumentOutOfRangeException("value");
+
+				if (value != selectedCharacterIndex)
+				{
+					string oldSelectedCharacter = SelectedCharacter;
+
+					selectedCharacterIndex = value;
+
+					string newSelectedCharacter = SelectedCharacter;
+
+					NotifyPropertyChanged();
+					if (newSelectedCharacter != oldSelectedCharacter) NotifyPropertyChanged("SelectedCharacter");
+					selectedCharacterInfo.Character = newSelectedCharacter;
+				}
+			}
+		}
+
+		public string SelectedCharacter
+		{
+			get { return selectedCharacterIndex >= 0 ? characters[selectedCharacterIndex] : null; }
+		}
+
+		public CharacterInfoViewModel SelectedCharacterInfo
+		{
+			get { return selectedCharacterInfo; }
+		}
+	}
+}
@@ -6,11 +6,11 @@
 		xmlns:System="clr-namespace:System;assembly=mscorlib"
        xmlns:local="clr-namespace:UnicodeCharacterInspector"
        mc:Ignorable="d"
-        Title="MainWindow"
+        Title="Unicode character inspector"
 		Background="{DynamicResource {x:Static SystemColors.ControlBrushKey}}"
 		Height="350" Width="525">
 	<Window.DataContext>
-		<local:CharacterInfoViewModel />
+		<local:CharacterInspectorViewModel />
 	</Window.DataContext>
    <Grid Margin="10">
 		<Grid.Resources>
@@ -23,6 +23,9 @@
 			<Style TargetType="{x:Type TextBlock}" BasedOn="{StaticResource ResourceKey={x:Type TextBlock}}">
 				<Setter Property="Margin" Value="3" />
 			</Style>
+			<Style TargetType="{x:Type ListBox}" BasedOn="{StaticResource ResourceKey={x:Type ListBox}}">
+				<Setter Property="Margin" Value="3" />
+			</Style>
 		</Grid.Resources>
 		<Grid.RowDefinitions>
 			<RowDefinition Height="Auto" />
@@ -34,20 +37,14 @@
 		<Grid.ColumnDefinitions>
 			<ColumnDefinition Width="*" />
 			<ColumnDefinition Width="*" />
+			<ColumnDefinition Width="*" />
 		</Grid.ColumnDefinitions>
-		<TextBox Grid.Row="0" Grid.ColumnSpan="2" MaxLength="2" MaxLines="1">
-			<TextBox.Text>
-				<Binding Path="Character" UpdateSourceTrigger="PropertyChanged">
-					<Binding.ValidationRules>
-						<ExceptionValidationRule />
-					</Binding.ValidationRules>
-				</Binding>
-			</TextBox.Text>
-		</TextBox>
-		<TextBlock Grid.Row="1" Grid.ColumnSpan="2" Text="{Binding Character}" FontSize="96" HorizontalAlignment="Center" VerticalAlignment="Center" />
-		<Label Grid.Row="2" Grid.Column="0" Content="Code point" />
-		<TextBlock Grid.Row="2" Grid.Column="1" Text="{Binding CodePoint, StringFormat=U+{0:X4}, TargetNullValue={x:Static System:String.Empty}}" VerticalAlignment="Center" />
-		<Label Grid.Row="3" Grid.Column="0" Content="Category" />
-		<TextBlock Grid.Row="3" Grid.Column="1" Text="{Binding Category}" VerticalAlignment="Center" />
+		<TextBox Grid.ColumnSpan="3" MaxLines="1" Text="{Binding Text, UpdateSourceTrigger=PropertyChanged}" />
+		<ListBox Grid.Row="1" Grid.RowSpan="4" ItemsSource="{Binding Characters}" SelectedIndex="{Binding SelectedCharacterIndex}" />
+		<TextBlock Grid.Row="1" Grid.Column="1" Grid.ColumnSpan="2" Text="{Binding SelectedCharacterInfo.Character}" FontSize="96" HorizontalAlignment="Center" VerticalAlignment="Center" />
+		<Label Grid.Row="2" Grid.Column="1" Content="Code point" />
+		<TextBlock Grid.Row="2" Grid.Column="2" Text="{Binding SelectedCharacterInfo.CodePoint, StringFormat=U+{0:X4}, TargetNullValue={x:Static System:String.Empty}}" VerticalAlignment="Center" />
+		<Label Grid.Row="3" Grid.Column="1" Content="Category" />
+		<TextBlock Grid.Row="3" Grid.Column="2" Text="{Binding SelectedCharacterInfo.Category}" VerticalAlignment="Center" />
    </Grid>
 </Window>
@@ -63,6 +63,7 @@
    </Compile>
    <Compile Include="BindableObject.cs" />
    <Compile Include="CharacterInfoViewModel.cs" />
+    <Compile Include="CharacterInspectorViewModel.cs" />
    <Compile Include="MainWindow.xaml.cs">
      <DependentUpon>MainWindow.xaml</DependentUpon>
      <SubType>Code</SubType>