I am unsure about how to remove cases from the "select case" statement in visual basic after a certain case has been selected more than 3 times - vb.net

Question

I've a word guessing game in development. It works so that when the play button is clicked, a random number between 1 and 20 will be generated. This new randomly generated number will then go into the select case statement as shown in the code below:
Dim RND As New Random
Dim rndNumber As String
rndNumber = RND.Next(1, 20)
Dim RndWord as string
Dim RndHint as string
select case(rndnumber)
case 1
RndWord = "hockey"
RndHint = "A ball game played with curved, wooden sticks"
Case 2
RndWord = "dinghy"
RndHint = "This is a small boat usually made out of rubber"
These are just 2 out of 20 similar cases.
The selected case contains a word and a hint that will be displayed upon that case being selected. My problem is, how do I remove a case after it has been selected three times; removing the word and the hint from the program completely so that they won't appear again. I've looked into different types of arrays; however, after 2 hours of research and many attempts at using them they don't seem to fit this purpose.

Answer 1

Firstly remove your case statement, it makes is less manageable. What if tomorrow you decide to add 5 more questions? You will end up changing the code. You can keep all the data externally and have them read into a dictionary object.
Define these at class level:
Dim questions As Dictionary(Of Integer, KeyValuePair(Of String, String)) = New Dictionary(Of Integer, KeyValuePair(Of String, String))()
Dim questionAppearedCount As Dictionary(Of Integer, Integer) = New Dictionary(Of Integer, Integer)()
Create new Sub with this:
Public Sub FillQuestions()
questions.Add(1, New KeyValuePair(Of String, String)("hockey", "A ball game played with curved, wooden sticks"))
questions.Add(2, New KeyValuePair(Of String, String)("dinghy", "This is a small boat usually made out of rubber"))
'Also, you may use File.ReadAllLines() to fill from a file.
End Sub
Finally, BtnGenerate_Click
Dim rnd As Random = New Random()
Dim rndNumber As Integer = rnd.[Next](1, 20)
If questionAppearedCount.ContainsKey(rndNumber) Then
questionAppearedCount(rndNumber) = questionAppearedCount(rndNumber) + 1
Else
questionAppearedCount.Add(rndNumber, 1)
End If
If questionAppearedCount(rndNumber) > 3 Then
'do not show question, instead get Next random
Else
return question(rndNumber)
End If
Here is the code, so I keep questions in dictionary, show them using dictionary.
In the above code, question can be read from external file using File.ReadAllLines()
When question is shown, add to the count and if count is > 3, don't show.

Answer 2

Make an array to count each case.
If the count is 3 you loop.
If less you increase the counter in the array and exit the loop so it ll use a case statement.
Be carreful in this case if all counters reach 3 the program wil loop infinitively.
Else an array for all the cases data.
When 3 is reached the datas are moved at the end of the array and the max index is decreased by one. At beginning its 20... next 19.. etc...

Answer 3

I recommend this code.
My sample also has a list of questions.
A very important differences though:
It does the filtering of the data BEFORE the random call. So, it's only searching for the questions that are valid. In certain cases, repeated random calls very close together might produce the same result, so this verifies you only do it once.
Imports System
Imports System.Collections
Imports System.Collections.Generic
Imports System.Linq
Public Module Module1
Dim questionAppearedCount As Dictionary(Of Integer, Integer)
Public Sub Main()
Dim questions As Dictionary(Of Integer, KeyValuePair(Of String, String)) = New Dictionary(Of Integer, KeyValuePair(Of String, String))()
questions.Add(1, New KeyValuePair(Of String, String)("hockey", "A ball game played with curved, wooden sticks"))
questions.Add(2, New KeyValuePair(Of String, String)("dinghy", "This is a small boat usually made out of rubber"))
questionAppearedCount = New Dictionary(Of Integer, Integer)()
SelectQuestion(1)
SelectQuestion(1)
SelectQuestion(1)
' Get the Filtered List
Dim filteredQuestions() as KeyValuePair(Of Integer, KeyValuePair(Of String, String)) = questions.Where(Function(ByVal item as KeyValuePair(Of Integer, KeyValuePair(Of String, String))) Not questionAppearedCount.ContainsKey(item.Key) OrElse questionAppearedCount(item.Key) < 3).ToArray()
Dim rand As New Random
Console.WriteLine(filteredQuestions(rand.Next(0, filteredQuestions.Count - 1)).Value)
End Sub
Public Sub SelectQuestion(ByVal questionNumber as Integer)
' Add Question
If questionAppearedCount.ContainsKey(questionNumber) Then
questionAppearedCount(questionNumber) += 1
Else
questionAppearedCount(questionNumber) = 1
End If
End Sub
End Module
And here's some vb.net helper code that you can use to REFACTOR your case statements automatically. Just paste your code into it and it will return the equivalent code to the console. You'll replace your code with this code.
Imports System
Imports System.Collections
Imports System.Collections.Generic
Imports System.Linq
Public Module Module1
Dim questionAppearedCount As Dictionary(Of Integer, Integer)
Public Sub Main()
'Dim questions as New Dictionary(Of Integer, KeyValuePair(Of String, String))
For rndnumber as Integer = 1 to 20
Dim RndWord as String = ""
Dim RndHint as String = ""
select case(rndnumber)
case 1
RndWord = "hockey"
RndHint = "A ball game played with curved, wooden sticks"
Case 2
RndWord = "dinghy"
RndHint = "This is a small boat usually made out of rubber"
end SElect
If Not String.IsNullOrEmpty(rndword) Then
'questions.Add(rndnumber, new KeyValuePair(Of String, String)(rndword, rndhint))
Console.WriteLine("questions.Add(" & rndnumber & ", new KeyValuePair(Of String, String)(""" & rndword.Replace("""", """""") & """,""" & RndHint.Replace("""", """""") & """))")
End If
Next
End Sub
End Module