''' <summary>
    ''' Implements a kind of Question/Answer KeyValuePair. 
    ''' This class cannot be inherited.
    ''' </summary>
    Public NotInheritable Class QA
 
        ''' <summary>
        ''' Gets the question.
        ''' </summary>
        ''' <value>The question.</value>
        ReadOnly Property Question As String
            Get
                Return Me.mQuestion
            End Get
        End Property
        Private mQuestion As String
 
        ''' <summary>
        ''' Gets the answer.
        ''' </summary>
        ''' <value>The answer.</value>
        ReadOnly Property Answer As String
            Get
                Return Me.mAnswer
            End Get
        End Property
        Private mAnswer As String
 
        ''' <summary>
        ''' Initializes a new instance of the <see cref="QA"/> class.
        ''' </summary>
        ''' <param name="question">The question.</param>
        ''' <param name="answer">The answer.</param>
        ''' <exception cref="System.ArgumentNullException">
        ''' question;value cannot be empty.
        ''' or
        ''' answer;value cannot be empty.
        ''' </exception>
        Public Sub New(ByVal question As String, ByVal answer As String)
 
            If String.IsNullOrEmpty(question) Then
                Throw New ArgumentNullException("question", "value cannot be empty.")
 
            ElseIf String.IsNullOrEmpty(answer) Then
                Throw New ArgumentNullException("answer", "value cannot be empty.")
 
            Else
                Me.mQuestion = question
                Me.mAnswer = answer
 
            End If
 
        End Sub
 
        ''' <summary>
        ''' Prevents a default instance of the <see cref="QA"/> class from being created.
        ''' </summary>
        Private Sub New()
        End Sub
 
    End Class

Public Class TestForm
 
    ''' <summary>
    ''' The Question/Answer list.
    ''' </summary>
    Public ReadOnly QAlist As New List(Of QA) From {
        New QA(question:="pregunta1", answer:="7"),
        New QA(question:="pregunta2", answer:="9"),
        New QA(question:="pregunta3", answer:="5")
    }
 
    ''' <summary>
    ''' Handles the Load event of the TestForm form.
    ''' </summary>
    Private Sub TestForm_Load(ByVal sender As Object, ByVal e As EventArgs) _
    Handles MyBase.Load
 
        ' Add the questions into Listbox.
        Me.ListBox1.Items.AddRange((From qa As QA In QAlist Select qa.Question).ToArray)
 
    End Sub
 
    ''' <summary>
    ''' Handles the SelectedIndexChanged event of the ListBox1 control.
    ''' </summary>
    Private Sub ListBox1_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs) _
    Handles ListBox1.SelectedIndexChanged
 
        Dim lb As ListBox = DirectCast(sender, ListBox)
        If Not lb.SelectionMode = SelectionMode.One Then
            Throw New NotImplementedException("SelectionMode is not implemented.")
        End If
 
        Dim qa As QA = QAlist.Find(Function(x As QA) x.Question.Equals(lb.SelectedItem.ToString))
 
        Debug.WriteLine(String.Format("Q: {0}", qa.Question))
        Debug.WriteLine(String.Format("A: {0}", qa.Answer))
        Debug.WriteLine(String.Empty)
 
    End Sub
 
End Class

using Microsoft.VisualBasic;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Diagnostics;
 
/// <summary>
/// Implements a kind of Question/Answer KeyValuePair. 
/// This class cannot be inherited.
/// </summary>
public sealed class QA
{
 
	/// <summary>
	/// Gets the question.
	/// </summary>
	/// <value>The question.</value>
	public string Question {
		get { return this.mQuestion; }
	}
	private string mQuestion;
 
	/// <summary>
	/// Gets the answer.
	/// </summary>
	/// <value>The answer.</value>
	public string Answer {
		get { return this.mAnswer; }
	}
	private string mAnswer;
 
	/// <summary>
	/// Initializes a new instance of the <see cref="QA"/> class.
	/// </summary>
	/// <param name="question">The question.</param>
	/// <param name="answer">The answer.</param>
	/// <exception cref="System.ArgumentNullException">
	/// question;value cannot be empty.
	/// or
	/// answer;value cannot be empty.
	/// </exception>
	public QA(string question, string answer)
	{
		if (string.IsNullOrEmpty(question)) {
			throw new ArgumentNullException("question", "value cannot be empty.");
 
		} else if (string.IsNullOrEmpty(answer)) {
			throw new ArgumentNullException("answer", "value cannot be empty.");
 
		} else {
			this.mQuestion = question;
			this.mAnswer = answer;
 
		}
 
	}
 
	/// <summary>
	/// Prevents a default instance of the <see cref="QA"/> class from being created.
	/// </summary>
	private QA()
	{
	}
 
}
 
//=======================================================
//Service provided by Telerik (www.telerik.com)
//=======================================================

using Microsoft.VisualBasic;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Diagnostics;
 
public class TestForm
{
 
	/// <summary>
	/// The Question/Answer list.
	/// </summary>
	public readonly List<QA> QAlist = new List<QA> {
		new QA(question: "pregunta1", answer: "7"),
		new QA(question: "pregunta2", answer: "9"),
		new QA(question: "pregunta3", answer: "5")
 
	};
 
	/// <summary>
	/// Handles the Load event of the TestForm form.
	/// </summary>
	private void TestForm_Load(object sender, EventArgs e)
	{
		// Add the questions into Listbox.
		this.ListBox1.Items.AddRange((from qa in QAlistqa.Question).ToArray);
 
	}
 
	/// <summary>
	/// Handles the SelectedIndexChanged event of the ListBox1 control.
	/// </summary>
	private void ListBox1_SelectedIndexChanged(object sender, EventArgs e)
	{
		ListBox lb = (ListBox)sender;
		if (!(lb.SelectionMode == SelectionMode.One)) {
			throw new NotImplementedException("SelectionMode is not implemented.");
		}
 
		QA qa = QAlist.Find((QA x) => x.Question.Equals(lb.SelectedItem.ToString));
 
		Debug.WriteLine(string.Format("Q: {0}", qa.Question));
		Debug.WriteLine(string.Format("A: {0}", qa.Answer));
		Debug.WriteLine(string.Empty);
 
	}
	public TestForm()
	{
		Load += TestForm_Load;
	}
 
}
 
//=======================================================
//Service provided by Telerik (www.telerik.com)
//=======================================================

Q: pregunta1
A: 7

Q: pregunta2
A: 9

Q: pregunta3
A: 5