Dot Net

Spotfire: How to add Gaussian Curve Fit to a chart using C# or IronPython code

2022-02-08T08:13:00.002-06:00

Here is a Spotfire ScatterPlot with a Gaussian Curve.

It is straightforward to add it from the UI by right clicking on the chart, opening up properties dialog and adding a Gaussian Curve Fir from the Lines & Curves section:

Here is how you would add it from the code:

var gaussianFittingModel = scatterPlot.FittingModels.AddNew<GaussianFittingModel>();

Spotfire: How to create Chart Categorical expression with Display Name? (C#, IronPython)

2021-12-21T14:58:00.005-06:00

Example of Categorical Expression with Display Name

This works:

$"<LandQuality{duration} as [Land Quality]>"

This doesn't work:

$"<LandQuality{duration}> as [Land Quality]"

Example:

BarChart.XAxis.Expression = $"<LandQuality{duration} as [Land Quality]>";

Let's compare this to Continuous Expression

BarChart.XAxis.Expression = $"[LandQuality{duration}] as [Land Quality]";

Spotfire: How to set Combination Chart Series color? IronPython C#

2021-12-13T11:01:00.001-06:00

combinationChart.ColorAxis.Coloring.Clear();

var categories = combinationChart.ColorAxis.Coloring.AddCategoricalColorRule().GetExplicitCategories();

foreach (var categoryKey in categories)

{

// Your business rules here ...

if(categoryKey.ToString().Contains("completion"))

combinationChart.ColorAxis.Coloring.SetColorForCategory(categoryKey, ColorTranslator.FromHtml("#17295f"));

else if(categoryKey.ToString().Contains("location"))

combinationChart.ColorAxis.Coloring.SetColorForCategory(categoryKey, ColorTranslator.FromHtml("#f51908"));

else

combinationChart.ColorAxis.Coloring.SetColorForCategory(categoryKey, ColorTranslator.FromHtml("#232323"));

}

Spotfire Data Limiting - How to limit data using markings (C#, Ironpython)

2021-12-13T09:39:00.002-06:00

Code:

public static void LimitDataUsingMarking(this Visualization chart, Document document)

{

chart.Data.Filterings.Add(document.Data.Markings["Marking"]);

}

Spotfire CombinationChart Setting Series Type (Bar or Line) C# IronPython

2021-12-10T08:50:00.002-06:00

IndexedCombinationChartSeriesType indexedSeriesType = combinationChart.IndexedSeriesType;

indexedSeriesType[new CategoryKey("BOE (Mstb)")] = CombinationChartSeriesType.Line;

Spotfire How to control number of decimals displayed on Value Axis? How to apply number format to Chart axis?

2021-08-10T10:53:00.002-05:00

If you want to apply a specific number format to the Spotfire Chart Axis, here is how you can accomplish it using the C# code:

if (DataType.Real.CreateLocalizedFormatter() is NumberFormatter realFormatter)

{

realFormatter.DecimalDigits = 5; // Number of decimals

barChart.YAxis.Scale.Formatting.RealFormatter = realFormatter;

}

Here is how you can apply this changes in Spotfire:

Spotfire ScatterPlot Set Color By Category (C#, IronPython)

2021-07-27T11:47:00.003-05:00

var coloring = scatterPlot.ColorAxis.Coloring;

coloring.Clear();

coloring.DefaultColor = Color.White;

var categoricalColorRule = coloring.AddCategoricalColorRule();

var colorKeys = categoricalColorRule.GetExplicitCategories();

scatterPlot.ColorAxis.Coloring.SetColorForCategory(colorKeys[0], Color.ForestGreen);

scatterPlot.ColorAxis.Coloring.SetColorForCategory(colorKeys[1], Color.Blue);

scatterPlot.ColorAxis.Coloring.SetColorForCategory(colorKeys[2], Color.Orange);

Images not showing up in Spotfire JSViz

2021-06-22T10:52:00.002-05:00

- Images with relative path will not show up in Spotfire JSViz

- Either use absolute path for the image or <img src="https://www.w3schools.com/images/picture.jpg" alt="Mountain">

- Base64 encode image data and use it https://css-tricks.com/data-uris/

How to base64 encode images for web pages?

2021-06-21T13:14:00.002-05:00

https://css-tricks.com/data-uris/

Spotfire LayoutDefinition Example

2021-06-10T15:32:00.004-05:00

Reference: Spotfire LayoutDefinition Class

Spotfire JSViz: How to Show or Hide Title of the visualization (C# extensions)

2021-06-09T10:28:00.003-05:00

var jsVisual = document.ActivePageReference.Visuals.AddNew<JSVisualizationModel>();

jsVisual.LegendVisible = false;

jsVisual.Visual.ShowTitle = false;

Updating Angular Version in your Project (i.e. from 10 to 12)

2021-06-08T10:53:00.003-05:00

https://update.angular.io/?v=10.0-12.0

WPF Telerik RadGridView Two Way DataBound CheckBox column

2021-03-22T11:39:00.003-05:00

<telerik:GridViewColumn Header="Update on PropertyChanged" Width="60" IsReadOnly="True">

<telerik:GridViewColumn.CellTemplate>

<DataTemplate>

<CheckBox HorizontalAlignment="Center" IsChecked="{Binding IsSelected, Mode=TwoWay}"/>

</DataTemplate>

</telerik:GridViewColumn.CellTemplate>

</telerik:GridViewColumn>

ASP.Net Web Forms: How to download a file? How to save string to a file?

2020-10-28T15:58:00.000-05:00

private void SaveFile(string featureKey)

{
Response.ContentType = "text/plain";
Response.AppendHeader("Content-Disposition", "attachment; filename=FeatureKey.txt");

if (Response.IsClientConnected)
{
var buffer = Encoding.ASCII.GetBytes(featureKey);
var length = featureKey.Length;
Response.OutputStream.Write(buffer, 0, length);
}

Response.Flush();
Response.End();

}

WPF: How to pass WindowHandle to ViewModel using MVVM pattern

2020-10-08T13:24:00.004-05:00

Create a Behavior with dependency property as shown below:

using System;

using System.Diagnostics.CodeAnalysis;

using System.Windows;

using System.Windows.Interactivity;

using System.Windows.Interop;

namespace My.Windows.Controls.Behaviors

{

[ExcludeFromCodeCoverage]

public class WindowHandleMVVMBehavior : Behavior<Window>

{

public IntPtr WindowHandle

{

get { return (IntPtr)GetValue(WindowHandleProperty); }

set { SetValue(WindowHandleProperty, value); }

}

public static readonly DependencyProperty WindowHandleProperty =

DependencyProperty.Register("WindowHandle", typeof(IntPtr), typeof(WindowHandleMVVMBehavior),

new FrameworkPropertyMetadata(IntPtr.Zero, FrameworkPropertyMetadataOptions.BindsTwoWayByDefault));

protected override void OnAttached()

{

base.OnAttached();

if (AssociatedObject != null)

{

AssociatedObject.Loaded += OnWindowLoaded;

}

private void OnWindowLoaded(object sender, RoutedEventArgs e)

{

var window = sender as Window;

var windowHandle = GetWindowHandle(window);

WindowHandle = windowHandle;

}

protected override void OnDetaching()

{

base.OnDetaching();

if (AssociatedObject != null)

{

AssociatedObject.Loaded -= OnWindowLoaded;

}

private IntPtr GetWindowHandle(Window window)

{

return window is null ? IntPtr.Zero : new WindowInteropHelper(window).Handle;

}

Use the Behavior in XAML like this:

<Window x:Class="Applications.Views.MainView"

xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity">

<i:Interaction.Behaviors>

<behaviors:WindowHandleMVVMBehavior WindowHandle="{Binding WindowHandle, Mode=TwoWay}"/>

</i:Interaction.Behaviors>

</Window>

Create Property in your ViewModel (DataContext of MainView) similar to this one:

private IntPtr _windowHandle;

public IntPtr WindowHandle

{

get { return _windowHandle; }

set

{

_windowHandle = value;

}

C# How to Serialize/Deserialize BitVector32

2013-06-14T14:19:00.000-05:00

I have a class with a property of type BitVector32, when I Serialize it, I noticed the property was not getting serialized because the BitVector32 is not [Serializable].

After thinking about how can I serialize this property and looking into the implementation of BitVector32 it became clear that I need to approach this from a different angle.

BitVector32 class has a property called Data where the information is stored, this property is of type Int and Int is obviously [Serializable].

Here is my approach:

[Serializable]
    public class TreeItem
    {
        // Serializable requires an empty constructor 
        public TreeItem()
        {
        }
 
        public int Id { get; set; }
        public int ObjectType { get; set; }
 
        [XmlIgnore]
        public BitVector32 Properties { get; set; }
 
        [XmlElement("Properties")]
        public Int32 Data
        {
            get { return Properties.Data; }
            set { Properties = new BitVector32(value); }
        }
    }

Here is how the serialized class looks like:

 <TreeItem xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">  
  <Id>1</Id>  
  <ObjectType>2</ObjectType>  
  <Properties>3</Properties>  
 </TreeItem>

Here is the test class:

using System.Collections.Specialized;
using System.IO;
using System.Linq;
using ComplexSerialization.IO;
using ComplexSerialization.Model;
using Microsoft.VisualStudio.TestTools.UnitTesting;
 
namespace Serialization.Tests
{
    [TestClass]
    public class TreeItemTest
    {
        public TestContext TestContext { get; set; }
 
        private XmlSerializer<TreeItem> _subject;
 
        private string _filePath;
 
        [TestInitialize]
        public void TestInitialize()
        {
            _subject = new XmlSerializer<TreeItem>();
            _filePath = Path.Combine(TestContext.TestDeploymentDir, "TreeItem.xml");
        }
 
        [TestMethod]
        public void Serialize()
        {
            // Arrange
            var treeItem = new TreeItem 
            { 
                Id = 1,
                ObjectType = 2,
                Properties = new BitVector32(3) 
            };
 
            // Act
            _subject.Serialize(treeItem, _filePath);
 
            // Assert
            Assert.AreEqual(1, Directory.GetFiles(TestContext.TestDeploymentDir).ToList().Count(x=>x.Contains("TreeItem.xml")));
        }
    }
}

WPF Telerik RadTreeView Select Node on right click

2013-05-13T15:02:00.000-05:00

In an application that we are working on, we want to select the Telerik RadTreeViewItem node the user is right clicking on and display context menu for the selected node.

This is not supported out of the box by Telerik, so I wrote an attached property to accomplish this. Please take a look at the code snippet below.

Full Visual Studio 2010 solution is also uploaded on my google drive here.

<Window x:Class="RadTreeViewExtensions.MainWindow" 
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:Telerik="http://schemas.telerik.com/2008/xaml/presentation"
        xmlns:RadTreeViewExtensions="clr-namespace:RadTreeViewExtensions"
        Title="Telerik RadTreeView Behavior: Select Node on right click " 
        Height="350" Width="525">
    <Grid>
        <Grid.Resources>
            <HierarchicalDataTemplate x:Key="ChildrenTemplate" ItemsSource="{Binding Path=Children}">
                <StackPanel>
                    <TextBlock Text="{Binding Name}" />
                </StackPanel>
            </HierarchicalDataTemplate>
        </Grid.Resources>
        <Telerik:RadTreeView ItemsSource="{Binding Items}" 
                             ItemTemplate="{StaticResource ChildrenTemplate}"
                             SelectionMode="Single" 
                             RadTreeViewExtensions:RadTreeViewBehavior.RightClickSelectsNode="True"/>
    </Grid>
</Window>

C# How to unit test Dispatcher

2013-04-10T09:27:00.002-05:00

Dispatcher provides services for managing the queue of work items for a thread. Sometimes to execute a task on a background thread.

Any task executed by calling Dispatcher.BeginInvoke(...) in unit test does not get executed until you do some wire-up.

This is how you would unit test code with Dispatcher.

using System;
using System.Windows.Threading;
using Microsoft.VisualStudio.TestTools.UnitTesting;
 
namespace UnitTesting.Tests
{
    [TestClass]
    public class DispatcherUtilTest
    {
        private ClassThatUsesDispatcher _subject;
        [TestInitialize]
        public void TestInitialize()
        {
            _subject = new ClassThatUsesDispatcher();
        }
 
        [TestMethod]
        public void UseDispatcher()
        {
            // Arrange
            var backgroundWorkDone = false;
            _subject.BackgroungWorkAction = () => { backgroundWorkDone = true; };
 
            // Act
            _subject.DoWork();
 
            // Assert
            // Without calling DispatcherUtil.DoEvents() the test will fail
            DispatcherUtil.DoEvents();
            Assert.IsTrue(backgroundWorkDone);
        }
 
        [TestMethod]
        public void DontUseDispatcher()
        {
            // Arrange
            var backgroundWorkDone = false;
            _subject.BackgroungWorkAction = () => { backgroundWorkDone = true; };
 
            // Act
            _subject.DoWork();
 
            // Assert
            Assert.IsFalse(backgroundWorkDone);
        }
    }
 
    internal class ClassThatUsesDispatcher
    {
        internal Action BackgroungWorkAction;
        readonly Dispatcher _dispatcher;
        internal ClassThatUsesDispatcher()
        {
             _dispatcher = Dispatcher.CurrentDispatcher;
             BackgroungWorkAction = DoSomeBackgroundWork;
        }
 
        public void DoWork()
        {
            _dispatcher.BeginInvoke(BackgroungWorkAction, DispatcherPriority.Background, new object[]{});
        }
 
        internal void DoSomeBackgroundWork()
        {
            // Make a web-service call
            // Read data from file-system
            // Wait for a resource
            // etc.
        }
    }
}

**** This is the class you would need to unit test Dispatcher ****

/// This class helps UnitTest Dispatcher.
/// Dispatcher does not automatically process its queue, 
/// DoEvents method here will tell the Dispatcher to process its queue

using System.Security.Permissions;
using System.Windows.Threading;
 
namespace UnitTesting
{
    public static class DispatcherUtil
    {
        [SecurityPermissionAttribute(SecurityAction.Demand, 
            Flags = SecurityPermissionFlag.UnmanagedCode)]
        public static void DoEvents()
        {
            var frame = new DispatcherFrame();
            Dispatcher.CurrentDispatcher.BeginInvoke(DispatcherPriority.Background,
                                                     new DispatcherOperationCallback(ExitFrame), frame);
            Dispatcher.PushFrame(frame);
        }
 
        private static object ExitFrame(object frame)
        {
            ((DispatcherFrame) frame).Continue = false;
            return null;
        }
    }
}

WPF How to Dispose ViewModel when the associated UserControl (Not Window) closes?

2013-03-01T14:36:00.001-06:00

Note: If your WPF UserControl is hosted in MFC Window, you may want to clean-up the ViewModel that is DataContext of your UserControl.

Since Unloaded event is not called reliably for the UserControl when the hosting MFC Window closes, there is a need for another solution.

XAML:

<UserControl x:Class="Views.MyUserControl"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             mc:Ignorable="d" 
             d:DesignHeight="300" d:DesignWidth="300">
    <Grid>
            
    </Grid>
</UserControl>

Code Behind:

using System;
using ViewModels;
 
namespace Views
{
    public partial class MyUserControl
    {
        public MyUserControl()
        {
            DataContext = new MyUserControlViewModel();
            InitializeComponent();
            Dispatcher.ShutdownStarted += OnDispatcherShutDownStarted;
        }
 
        private void OnDispatcherShutDownStarted(object sender, EventArgs e)
        {
            var disposable = DataContext as IDisposable;
            if (!ReferenceEquals(null, disposable))
            {
                disposable.Dispose();
            }
        }
    }
}


ViewModel:
using System;
 
namespace ViewModels
{
    public class MyUserControlViewModel : IDisposable
    {
        public void Dispose()
        {
            // Cleanup code
            // SettingsRepository.Save();
            // WebServiceConnection.Close();
            // etc.
        }
    }
}

C# How to create generic List with dynamic type

2013-02-27T08:52:00.000-06:00

 Given the Type typeof(Item) (defined below), how would you create a list of Items using Reflection in C#?

var type = typeof(Item);
IList listOfItems = (IList)Activator.CreateInstance(typeof(List<>).MakeGenericType(type));

public class Item

{
    public string Name { get; set; }
}

WPF InputBindings KeyBinding Command Example .Net 4.0

2013-02-08T10:53:00.002-06:00

WPF starting from .Net Framework 4.0 allows developers to bind commands directly to the KeyBindings as shown in the example below:

A complete solution is posted here on my Google Drive: https://docs.google.com/file/d/0Bw72YL7u1BpmaFdsSng1N3Rqbnc/edit?usp=sharing

<Window x:Class="WPF_InputBindings_Keybinding.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="WPF InputBindings KeyBindings Example" Height="400" Width="400" Focusable="True">
    <Window.InputBindings>

        <KeyBinding Key="C" Modifiers="Control" Command="{Binding CopyCommand}" />
        <KeyBinding Key="V" Modifiers="Control" Command="{Binding PasteCommand}" />
    </Window.InputBindings>
</Window>

WPF: How to Style Horizontal GridSplitter

2013-02-01T09:09:00.003-06:00

<Window x:Class="HorizontalGridSplitterExample"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="HorizontalGridSplitter Example" Height="300" Width="300">
    <Window.Resources>
        
        <Style x:Key="GridSplitterHorizontalGripStyle" TargetType="{x:Type GridSplitter}">
            <Setter Property="HorizontalAlignment" Value="Stretch" />
            <Setter Property="FocusVisualStyle" Value="{x:Null}" />
            <Setter Property="Cursor" Value="SizeNS" />
            <Setter Property="FocusVisualStyle" Value="{x:Null}" />
            <Setter Property="Background"
                    Value="{DynamicResource {x:Static SystemColors.ControlBrushKey}}" />
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="{x:Type GridSplitter}">
                        <Border BorderBrush="{TemplateBinding BorderBrush}"
                                BorderThickness="{TemplateBinding BorderThickness}"
                                Background="{TemplateBinding Background}"
                                Height="{TemplateBinding Height}">
                            <Border Width="50" Height="4" HorizontalAlignment="Center"
                                    BorderThickness="0 1" Background="White" BorderBrush="#A0A0A0">
                            </Border>
                        </Border>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
 
        <Style x:Key="HorizontalGridSplitter" TargetType="{x:Type GridSplitter}"
                BasedOn="{StaticResource GridSplitterHorizontalGripStyle}">
            <Setter Property="Height" Value="6" />
            <Setter Property="Margin" Value="0 15" />
            <Setter Property="HorizontalAlignment" Value="Stretch" />
        </Style>
    </Window.Resources>
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition />
            <RowDefinition Height="Auto" />
            <RowDefinition />
        </Grid.RowDefinitions>
        <Grid>
            <Border Background="LightBlue" />
        </Grid>
        
        <GridSplitter Grid.Row="1" Style="{StaticResource HorizontalGridSplitter}"/>
        <Grid Grid.Row="2">
            <Border Background="LightBlue" />
        </Grid>
    </Grid>
</Window>

WPF: How to Style Vertical GridSplitter

2013-02-01T09:04:00.003-06:00



<Window x:Class="VerticalGridSplitterExample"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="VerticalGridSplitter Example"
        Height="300" Width="300">
    <Window.Resources>
        
        <Style x:Key="GridSplitterVerticalGripStyle" TargetType="{x:Type GridSplitter}">
            <Setter Property="VerticalAlignment" Value="Stretch" />
            <Setter Property="FocusVisualStyle" Value="{x:Null}" />
            <Setter Property="Cursor" Value="SizeWE" />
            <Setter Property="FocusVisualStyle" Value="{x:Null}" />
            <Setter Property="Background"
                    Value="{DynamicResource {x:Static SystemColors.ControlBrushKey}}" />
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="{x:Type GridSplitter}">
                        <Border BorderBrush="{TemplateBinding BorderBrush}"
                                BorderThickness="{TemplateBinding BorderThickness}"
                                Background="{TemplateBinding Background}"
                                Width="{TemplateBinding Width}">
                            <Border Height="50" Width="4" VerticalAlignment="Center"
                                    HorizontalAlignment="Center" BorderThickness="1 0"
                                    Background="White" BorderBrush="#A0A0A0">
                            </Border>
                        </Border>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
 
        <Style x:Key="VerticalGridSplitter" TargetType="{x:Type GridSplitter}"
                BasedOn="{StaticResource GridSplitterVerticalGripStyle}">
            <Setter Property="Width" Value="6" />
            <Setter Property="Margin" Value="15 0" />
            <Setter Property="VerticalAlignment" Value="Stretch" />
            <Setter Property="HorizontalAlignment" Value="Center" />
        </Style>
    </Window.Resources>
    
    <Grid>
        <Grid.ColumnDefinitions>
            <ColumnDefinition />
            <ColumnDefinition Width="Auto" />
            <ColumnDefinition />
        </Grid.ColumnDefinitions>
        <Grid>
            <Border Background="LightBlue" />
        </Grid>
        <GridSplitter Grid.Column="1" Style="{StaticResource VerticalGridSplitter}" />
        <Grid Grid.Column="2">
            <Border Background="LightBlue" />
        </Grid>
    </Grid>
</Window>

WPF Drag & Drop: How to detect when drag is started

2013-01-24T10:26:00.000-06:00

This article will explain how to detect when drag is started in WPF Applications.

Features:

1) Reliably detect drag & drop

2) Don't confuse double clicks as drag start

3) Don't confuse scrolling as drag event

Notes:

- WPF is very powerful, but one thing i find missing is an event telling developers when drag is started

- The solution here involves handling Left Button Down, Mouse Move & Left Button Up event combinations to detect when drag & drop is started and when it ended

Important:

Even though the code posted here uses code-behind, I highly recommend using MVVM way of handling drag & drop using attached properties on controls to detect drag & drop, show visual feedback and transfer data. (I will post a WPF MVVM Drag & Drop Framework soon)

Complete Visual Studio 2010 Solution
https://docs.google.com/file/d/0Bw72YL7u1BpmQkl3Q3BleDgzR1E/edit?usp=sharing

XAML:

<Window x:Class="DragAndDropDragStart.MainWindow" 
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
        Title="WPF Drag and Drop: detect when drag is started" 
        Height="200" Width="200">
    <Grid>
        <TextBlock Text="Drag me!" 
                   HorizontalAlignment="Center" 
                   VerticalAlignment="Center" 
                   FontSize="25" Foreground="RoyalBlue" 
                   MouseLeftButtonDown="OnDragSourceMouseLeftButtonDown" 
                   MouseLeftButtonUp="OnDragSourceMouseLeftButtonUp" 
                   MouseMove="OnDragSourceMouseMove"/>
    </Grid>
</Window>

Code-Behind:

 using System;  
 using System.Windows;  
 using System.Windows.Controls.Primitives;  
 using System.Windows.Input;  
 using System.Windows.Media;  
 namespace DragAndDropDragStart  
 {  
   /// <summary>  
   /// Interaction logic for MainWindow.xaml  
   /// </summary>  
   public partial class MainWindow  
   {  
     private Point _dragStartPoint;  
     private bool _isMouseDown;  
     public MainWindow()  
     {  
       InitializeComponent();  
     }  
     private void OnDragSourceMouseLeftButtonDown(object sender,   
       MouseButtonEventArgs e)  
     {  
       if (e.ClickCount != 1)  
       {  
         return;  
       }  
       _dragStartPoint = e.GetPosition(e.Source as FrameworkElement);  
       _isMouseDown = true;  
     }  
     private void OnDragSourceMouseMove(object sender, MouseEventArgs e)  
     {  
       if (_isMouseDown &&   
         IsDragGesture(e.GetPosition(e.Source as FrameworkElement)))  
       {  
         if (ReferenceEquals(null,   
           FindAncestor<ScrollBar>((DependencyObject)e.OriginalSource)))  
         {  
           // Drag Started  
           _isMouseDown = false;  
           Mouse.Capture(sender as UIElement);  
           MessageBox.Show("Drag Started");  
         }  
       }  
     }  
     private void OnDragSourceMouseLeftButtonUp(object sender,   
       MouseButtonEventArgs e)  
     {  
       _isMouseDown = false;  
       Mouse.Capture(null);  
     }  
     private bool IsDragGesture(Point point)  
     {  
       var horizontalMove = Math.Abs(point.X - _dragStartPoint.X);  
       var verticalMove = Math.Abs(point.Y - _dragStartPoint.Y);  
       var hGesture = horizontalMove >  
               SystemParameters.MinimumHorizontalDragDistance;  
       var vGesture = verticalMove >  
               SystemParameters.MinimumVerticalDragDistance;  
       return (hGesture | vGesture);  
     }  
     private static T FindAncestor<T>(DependencyObject dependencyObject)  
       where T : DependencyObject  
     {  
       var parent = VisualTreeHelper.GetParent(dependencyObject);  
       if (parent == null) return null;  
       var parentT = parent as T;  
       return parentT ?? FindAncestor<T>(parent);  
     }  
   }  
 }

C# how to get type of generic class using reflection

2013-01-21T08:06:00.000-06:00

In the following example, given an instance of SystemFolder, how would you find the generic type 
Folder given that SystemFolder : IDropTarget<Folder>?

using System;
using System.Collections.ObjectModel;
using System.Diagnostics;
using System.Linq;
 
namespace CSharpGenerics
{

public class GenericUtilities
    {
        // Example Type type = GenericUtilities.GetGenericType(new SystemFolder()); will return Folder
        public static Type GetGenericType(object @object)
        {
            var type = @object.GetType();
            var iDropTargetObject = type.GetInterfaces().
FirstOrDefault(x => x.IsGenericType && x.GetGenericTypeDefinition() == typeof(IDropTarget<>));
            Debug.Assert(iDropTargetObject != null);
            return iDropTargetObject.GetGenericArguments()[0];
        }
    }

    public class SystemFolder : IDropTarget<Folder>
    {
        public SystemFolder()
        {
            Items = new Collection<Folder>();
        }
 
        public Collection<Folder> Items { get; set; }
 
        #region IDropTarget Members
 
        public string Name
        {
            get { return "My Drop Target"; }
        }
 
        public void Add(Folder item)
        {
            Items.Add(item);
        }
 
        #endregion IDropTarget Members
    }
 
    public class Folder
    {
    }
 
    public interface IDropTarget
    {
        string Name { get; }
 
        void Add(T item);
    }
}

Test Class

using Microsoft.VisualStudio.TestTools.UnitTesting;
 
namespace CSharpGenerics.Tests
{
    [TestClass]
    public class SystemFolderTest
    {
        [TestMethod]
        public void GetGenericType()
        {
            // Act
            var genericType = GenericUtilities.GetGenericType(new SystemFolder());
 
           // Assert
            Assert.AreEqual(genericType, typeof(Folder));
 
        }
    }
}