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Getting and setting large amount of text data in clipboard

I'm making simple tool app in C#, I have a textbox and I want to paste some text (around 300k lines), but this makes the app unresponsive. I waited like 10 minutes and nothing moved forward.
Is there some way to handle paste and copy operations on large data sets in smoother way? For example pasting and copying same amount of data in Windows Notepad takes just few seconds.
I use
Windows.ApplicationModel.DataTransfer.Clipboard.GetContent()
and at this app hangs.
Example Code
Xaml
<Window
x:Class="App2.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:App2"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d">
<Grid Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="1" Grid.RowSpan="1">
<Grid.RowDefinitions>
<RowDefinition/>
</Grid.RowDefinitions>
<ScrollViewer Grid.Row="0" Grid.RowSpan="1" Margin="5" VerticalScrollBarVisibility="Visible" >
<TextBox VerticalAlignment="Stretch" HorizontalAlignment="Stretch" IsReadOnly="False" Header="Query Result" Text='{x:Bind pasteResult, Mode=TwoWay}' PlaceholderText="Paste results here" TextWrapping="Wrap"/>
</ScrollViewer>
</Grid>
</Window>
cs file
using Microsoft.UI.Xaml;
using Microsoft.UI.Xaml.Controls;
using Microsoft.UI.Xaml.Controls.Primitives;
using Microsoft.UI.Xaml.Data;
using Microsoft.UI.Xaml.Input;
using Microsoft.UI.Xaml.Media;
using Microsoft.UI.Xaml.Navigation;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices.WindowsRuntime;
using Windows.Foundation;
using Windows.Foundation.Collections;
// To learn more about WinUI, the WinUI project structure,
// and more about our project templates, see: http://aka.ms/winui-project-info.
namespace App2
{
/// <summary>
/// An empty window that can be used on its own or navigated to within a Frame.
/// </summary>
public sealed partial class MainWindow : Window
{
public string pasteResult;
public MainWindow()
{
this.InitializeComponent();
}
}
}

As #Simon Mourier mentioned in the comments, the performance problem is not related to the clipboard, but the TextBox control processing that amount of data.
So, let me give you another option using the ItemsRepeater which comes with virtualization built-in. (In my laptop) it takes approx. 3 secs to show 500K lines of text from the clipboard.
MainWindow.xaml
<Window
x:Class="ClipboardTests.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d">
<Grid RowDefinitions="Auto,*">
<StackPanel
Grid.Row="0"
Orientation="Horizontal">
<Button
Click="PasteButton_Click"
Content="Paste" />
<Button
Click="ClearButton_Click"
Content="Clear" />
<TextBlock
x:Name="MessageTextBox"
VerticalAlignment="Center" />
</StackPanel>
<ScrollViewer Grid.Row="1">
<ItemsRepeater x:Name="TextItemsRepeaterControl" />
</ScrollViewer>
</Grid>
</Window>
MainWindow.xaml.cs
using Microsoft.UI.Xaml;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Threading.Tasks;
using Windows.ApplicationModel.DataTransfer;
namespace ClipboardTests;
public sealed partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private static async Task<IEnumerable<string>> GetTextLinesFromClipboard()
{
DataPackageView dataPackageView = Clipboard.GetContent();
if (dataPackageView.Contains(StandardDataFormats.Text) is true)
{
string text = await dataPackageView.GetTextAsync();
string[] lines = text
.ReplaceLineEndings()
.Split(Environment.NewLine, StringSplitOptions.None);
return lines;
}
return Enumerable.Empty<string>();
}
private async void PasteButton_Click(object sender, RoutedEventArgs e)
{
Stopwatch stopwatch = Stopwatch.StartNew();
IEnumerable<string> lines = await GetTextLinesFromClipboard();
this.TextItemsRepeaterControl.ItemsSource = lines;
stopwatch.Stop();
this.MessageTextBox.Text = $"Pasted {this.TextItemsRepeaterControl.ItemsSourceView.Count} items in {stopwatch.Elapsed.TotalSeconds} s.";
}
private void ClearButton_Click(object sender, RoutedEventArgs e)
{
this.TextItemsRepeaterControl.ItemsSource = null;
}
}

The Listbox items initialize but once one is selected I don't know how to RESET the listbox where neither item is selected

If you run the code neither of the list box items are selected. If you select either it remains selected okay and displays either "One" or "Two" in the text box accordingly. When the ResetListBox button is clicked the selected item is deselected (?maybe) but retains a grey background (undesired). Once the item has this light grey background the onClick event no longer fires... No additional text is added to the text box. This question has been asked in various forms all over the web and none of the answers that I've tried in this simple example has worked.
<Window x:Class="WpfApp1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:WpfApp1"
mc:Ignorable="d"
Title="MainWindow" Height="279.186" Width="401.98">
<Grid Margin="0,0,-6.8,-2.4">
<ListBox x:Name="ThanklessListBox" HorizontalAlignment="Left" Height="89" Margin="24,25,0,0" VerticalAlignment="Top" Width="117">
<ListBoxItem x:Name="ItemI" Content="ItemUno" Selected="ItemI_Selected"/>
<ListBoxItem x:Name="Item2" Content="ItemDos" Selected="Item2_Selected"/>
</ListBox>
<TextBox x:Name="StuffToShow" HorizontalAlignment="Left" Height="178" Margin="198,25,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="116"/>
<Button x:Name="ResetListBox" Content="ResetListBox" HorizontalAlignment="Left" Height="26" Margin="28,131,0,0" VerticalAlignment="Top" Width="116" Click="ResetListBox_Click"/>
<Button x:Name="SeleectButton" Content="SelectItemDos" HorizontalAlignment="Left" Height="24" Margin="28,179,0,0" VerticalAlignment="Top" Width="116" Click="SeleectButton_Click"/>
</Grid>
</Window>
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
namespace WpfApp1
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private void ItemI_Selected(object sender, RoutedEventArgs e)
{
StuffToShow.Text += "\nOne";
}
private void Item2_Selected(object sender, RoutedEventArgs e)
{
StuffToShow.Text += "\nTwo";
}
private void SeleectButton_Click(object sender, RoutedEventArgs e)
{
ThanklessListBox.SelectedItem = 1; //Choose Dos
}
private void ResetListBox_Click(object sender, RoutedEventArgs e)
{
ThanklessListBox.SelectedItem = -1; //Deselect
}
}

In your code behind, you are using SelectedItem with an integer.
private void ResetListBox_Click(object sender, RoutedEventArgs e)
{
ThanklessListBox.SelectedItem = -1; //Deselect
}
Try either using SelectedIndex
private void ResetListBox_Click(object sender, RoutedEventArgs e)
{
ThanklessListBox.SelectedIndex = -1; //Deselect
}
Or Selected Item with null
Edited to add: You could also do
ThanklessListBox.SelectedItems.Clear
which is what I think the other person whose post is now deleted meant>
In fairness, this is something you could really learn just by browsing the online documentation for ListBox on the MS site

Canvas to support a scrollable stock graph

I would like to draw a graph of a stock on a canvas.
The canvas has an initil size lets say 300 (height) x 1000 (Width).
The stock has been trading for more days that can fit into the visual part of the Canvas
I would like to drag (scroll) the visual part of the canvas around and see the non visual parts that are hidden "behind". i.e see trading days that are not initially displyed.
Would appreciate any ideas or pointers to get me on the right path.

You can use two canvases - a canvas inside a canvas. The outer canvas would be fixed in size (1000 x 300), but the inner canvas would be as large as you want it to be. Set the ClipToBounds property of the outer canvas to True.
C#:
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
namespace Stock
{
/// <summary>
/// Interaction logic for ListBox.xaml
/// </summary>
public partial class Chart : Window
{
private Point _capturePoint;
private double _captureLeft;
private double _captureTop;
public Chart()
{
InitializeComponent();
}
protected override void OnMouseLeftButtonDown(MouseButtonEventArgs e)
{
base.OnMouseLeftButtonDown(e);
_capturePoint = e.GetPosition(chart);
_captureLeft = Canvas.GetLeft(chart);
_captureTop = Canvas.GetTop(chart);
if (_capturePoint.X > 0 && _capturePoint.X < chart.RenderSize.Width &&
_capturePoint.Y > 0 && _capturePoint.Y < chart.RenderSize.Height)
{
CaptureMouse();
}
}
protected override void OnMouseLeftButtonUp(MouseButtonEventArgs e)
{
base.OnMouseLeftButtonUp(e);
ReleaseMouseCapture();
}
protected override void OnMouseMove(MouseEventArgs e)
{
base.OnMouseMove(e);
if (Mouse.Captured == this)
{
var currentPoint = e.GetPosition(chart);
var diff = Point.Subtract(currentPoint, _capturePoint);
Canvas.SetTop(chart, _captureTop + diff.Y);
Canvas.SetLeft(chart, _captureLeft + diff.X);
}
}
}
}
XAML:
<Window x:Class="Stock.Chart"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="ListBox" Height="300" Width="300">
<Canvas Height="300" Width="1000" x:Name="viewport" ClipToBounds="True">
<Canvas x:Name="chart" Background="Green" Width="2000" Height="1000" Canvas.Top="20" Canvas.Left="10" >
</Canvas>
</Canvas>
</Window>

C# WPF ChartingToolKit: How to get independent-axis value from ColumnSeries in MouseRightButtonDown?

I have a ColumnSeries with data bound to it and it displays correctly. When a column is right-clicked, I want to figure out what the independent-axis (X) value is. Ideally, I want to display a context menu with that information.
I have a MouseRightButtonDown handler, but cannot figure out how to perform the hit test to get the X-axis information.
I have selection enabled, but do not want to have to select a column prior to right-click.
Any help would be appreciated!

You can walk up the visual tree looking for a ColumnDataPoint.
Here's a sample graph:
<Grid MouseLeftButtonDown="Grid_MouseLeftButtonDown">
<Grid.Resources>
<PointCollection x:Key="sampleData">
<Point X="1" Y="6"/>
<Point X="2" Y="4"/>
<Point X="3" Y="8"/>
</PointCollection>
</Grid.Resources>
<chartingToolkit:Chart Title="Chart Title">
<chartingToolkit:ColumnSeries Name="chart1" Title="Column Series" ItemsSource="{StaticResource sampleData}" IndependentValueBinding="{Binding X}" DependentValueBinding="{Binding Y}"/>
</chartingToolkit:Chart>
</Grid>
and with this code-behind:
private void Grid_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
var element = Mouse.DirectlyOver as DependencyObject;
while (element != null && !(element is ColumnDataPoint))
{
element = VisualTreeHelper.GetParent(element);
}
if (element != null)
{
var columnDataPoint = element as ColumnDataPoint;
Debug.WriteLine("X = " + columnDataPoint.IndependentValue);
Debug.WriteLine("Y = " + columnDataPoint.DependentValue);
}
}
the X and Y values for the item the mouse is over will be printed out when the left mouse button is clicked.

Here is the example code that works.
MainWindow.xaml:
<Window x:Class="ColumnSeriesApp.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:chartingToolkit="clr-namespace:System.Windows.Controls.DataVisualization.Charting;assembly=System.Windows.Controls.DataVisualization.Toolkit"
xmlns:local="clr-namespace:ColumnSeriesApp"
Title="Pet Data" Height="350" Width="525">
MainWindow.xaml.cs:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
namespace ColumnSeriesApp
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public PetData m_PetData;
public MainWindow()
{
m_PetData = new PetData();
DataContext = m_PetData;
InitializeComponent();
}
private void m_colserHistogram_MouseRightButtonDown(object sender, MouseButtonEventArgs e)
{
// Figure out what column we are on and display a popup menu based on the information.
IInputElement ieMouseOver = e.MouseDevice.DirectlyOver;
Rectangle rMouseOver = (Rectangle)ieMouseOver;
string strMouseOverContext= rMouseOver.DataContext.ToString();
string strMouseOverKey= "";
foreach (var vKvP in m_PetData)
{
if (1 == strMouseOverContext.IndexOf(vKvP.Key))
strMouseOverKey = vKvP.Key;
}
if (!String.IsNullOrEmpty(strMouseOverKey))
MessageBox.Show("The X value is " + strMouseOverKey);
}
}
public class PetData : Dictionary<string, int>
{
public PetData()
{
Add("SallyBeagle", 7);
Add("Cujo", 10);
Add("DobyDeedle", 11);
Add("Caramel", 6);
Add("Boo", 6);
}
}
}
It seems to work pretty well. If Rick had not come back with an idea, I would probably have quit looking for awhile - thanks for the motivation!
Now - is this solution all MVVM and whatnot? It still feels a little like a hack....

How do I get rid of the red rectangle when my wpf binding validation has failed and the containing panel is no longer visible?

I have a situation where I am using wpf data binding and validation using the ExceptionValidationRule.
Another part of the solution invovles collapsing some panels and showing others.
If a validation exception is set - i.e. the UI is showing a red border around the UI element with the validation problem, and the containing panel is collapsed, the red border is still displayed. This is clearly not meant to be? Is there a workaround for this? Anyone know if this is by design?
Minimal code example provided (not my actual code, but replicates the problem). Create a new WpfApplication (I called mine WpfDataBindingProblem).
The xaml for window1 is as follows:
<Window x:Class="WpfDataBindingProblem.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Window1" Height="300" Width="300">
<StackPanel Margin="5">
<StackPanel Name="panel1" Visibility="Visible" Margin="5">
<TextBox Name="DataBoundTextBox">
<Binding Path="TextValue">
<Binding.ValidationRules>
<ExceptionValidationRule/>
</Binding.ValidationRules>
</Binding>
</TextBox>
</StackPanel>
<StackPanel Name="panel2" Visibility="Collapsed" Margin="5">
<TextBlock>
The quick brown fox jumps over the lazy dog.
</TextBlock>
</StackPanel>
<Button Click="Button_Click" Margin="5">
Toggle panels
</Button>
</StackPanel>
</Window>
The code for window1 is as follows:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
namespace WpfDataBindingProblem {
public partial class Window1 : Window {
public Window1() {
InitializeComponent();
this.DataContext = new MyClass("default");
}
private void Button_Click(object sender, RoutedEventArgs e) {
panel1.Visibility = panel1.Visibility == Visibility.Collapsed ?
Visibility.Visible : Visibility.Collapsed;
panel2.Visibility = panel2.Visibility == Visibility.Collapsed ?
Visibility.Visible : Visibility.Collapsed;
}
}
public class MyClass : INotifyPropertyChanged {
private string mTextValue;
public MyClass(string defaultText) {
TextValue = defaultText;
}
public string TextValue {
get {
return mTextValue;
}
set {
mTextValue = value;
if (string.IsNullOrEmpty(mTextValue)) {
throw new ApplicationException("Text value cannot be empty");
}
OnPropertyChanged(new PropertyChangedEventArgs("TextValue"));
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged(PropertyChangedEventArgs e) {
if (this.PropertyChanged != null) {
this.PropertyChanged(this, e);
}
}
}
}
To reproduce the problem, run the application. Delete the default text from the textbox and tab off - red rectangle is shown indicating a validation problem. Click the button. Panel containing control with red rectangle is hidden and another panel is shown, but the red rectangle remains. Aargh!
All help much appreciated.
PS apologies for long question title!

If I remember correctly, this is a known issue. We re-templated textbox to include the following:
<Setter Property="Validation.ErrorTemplate">
<Setter.Value>
<ControlTemplate>
<ControlTemplate.Resources>
<BooleanToVisibilityConverter x:Key="converter" />
</ControlTemplate.Resources>
<DockPanel LastChildFill="True">
<Border
BorderThickness="1"
BorderBrush="Red"
Visibility="{Binding ElementName=placeholder, Mode=OneWay, Path=AdornedElement.IsVisible, Converter={StaticResource converter}}">
<AdornedElementPlaceholder x:Name="placeholder" />
</Border>
</DockPanel>
</ControlTemplate>
</Setter.Value>
</Setter>

I have an answer to the problem myself which is to change my button click event which changes the visibility of the panels. This would change to something like this:
private void Button_Click(object sender, RoutedEventArgs e) {
if (panel1.Visibility == Visibility.Collapsed) {
panel1.Visibility = Visibility.Visible;
DataBoundTextBox.GetBindingExpression(TextBox.TextProperty).UpdateSource();
panel2.Visibility = Visibility.Collapsed;
}
else {
panel1.Visibility = Visibility.Collapsed;
DataBoundTextBox.GetBindingExpression(TextBox.TextProperty).UpdateTarget();
panel2.Visibility = Visibility.Visible;
}
}
The UpdateSource() and UpdateTarget() have the effect of reapplying and removing the red rectangle, but this seems like an ugly hack. Surely the wpf framework should be hiding the red rectangle for me when the containing panel is collapsed. Any cleaner fix that doesn't require me to fiddle with the binding expression gets my vote.
Thanks,
Sam