I have created a list of eight dynamic comboBoxes through the function combox1Gen() and then i have loaded items to them from a text file of values through function loadComboboxItems(). On every respective comboBox's item selection i need to display the value and its index. what code should in put inside ComboTName_SelectedIndexChanged()?
One more issue is there. My comboBoxes with items get loaded very slowly in a hanging way. whats wrong with my code?
My code is below:
Public ComboBoxesTname As New List(Of ComboBox)
Dim i As Integer = 0
Do While i <= 7
Combo1Gen(i)
i = i + 1
Loop
loadComboboxItems()
Private Function Combo1Gen(ByVal n As Integer) As Boolean
Try
Dim newCombo As New ComboBox
With newCombo
.Name = "MyComboBox1" & n.ToString
.Left = 110
.Top = 120 + (52 * n) + 20
.Width = 180
.Height = 20
.Visible = True
End With
ComboBoxesTname.Add(newCombo)
GroupBox1.Controls.Add(newCombo)
GroupBox1.AutoSize = True
AddHandler newCombo.SelectedIndexChanged, AddressOf ComboTName_SelectedIndexChanged
Return True
Catch ex As Exception
MessageBox.Show(ex.ToString)
Return False
End Try
End Function
Private Function loadComboboxItems() As Boolean
Try
Dim listT As New List(Of String)()
listT = ReadVars.readVars(GetFolderPath.GetFolderPath("\vars\"), "items.txt")
For i = 0 To ComboBoxesTname.Count - 1
ComboBoxesTname(i).Items.AddRange(listT.ToArray)
Next
Return True
Catch ex As Exception
Debug.WriteLine(ex.ToString)
MessageBox.Show("Error: " & Err.ToString)
Return False
End Try
Return False
End Function
Private Sub ComboTName_SelectedIndexChanged()
End Sub
I am not sure exactly what you want to do in SelectIndexChanged but I showed how to get the values from the combo that was clicked.
See comments and explanations in line.
Public ComboBoxesTname As New List(Of ComboBox)
Private Sub LoadCombos()
For i = 0 To 7
Combo1Gen(i)
Next
loadComboboxItems()
End Sub
'Since you never use the return value I changed this to a Sub
Private Sub Combo1Gen(ByVal n As Integer)
Dim newCombo As New ComboBox
With newCombo
.Name = "MyComboBox1" & n.ToString
.Left = 110
.Top = 10 + (52 * n) + 20
.Width = 180
.Height = 20
.Visible = True
End With
ComboBoxesTname.Add(newCombo)
GroupBox1.Controls.Add(newCombo)
GroupBox1.AutoSize = True
AddHandler newCombo.SelectedIndexChanged, AddressOf ComboTName_SelectedIndexChanged
End Sub
'Since I don't have access to ReadVars I created an arbitrary array to test
Private listT As String() = {"Mathew", "Mark", "Luke", "John"}
'You should have readVars return an array of strings
'Create this once as a Form level variable so you don't have to read the file over and over
'Private listT As String() = ReadVars.readVars(GetFolderPath.GetFolderPath("\vars\"), "items.txt")
'Since you never use the return value I changed this to a Sub
Private Sub loadComboboxItems()
For i = 0 To ComboBoxesTname.Count - 1
ComboBoxesTname(i).Items.AddRange(listT)
Next
End Sub
'Added the appropriate parameters
Private Sub ComboTName_SelectedIndexChanged(sender As Object, e As EventArgs)
'Cast sender to a ComboBox so we can use the Properties of a ComboBox
Dim Combo = DirectCast(sender, ComboBox)
Dim Name = Combo.Name
Dim Item = Combo.SelectedItem
MessageBox.Show($"The selected item in {Name} is {Item}")
End Sub
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
LoadCombos()
End Sub
EDIT
In response to your question in comments. I added a Function and a few changes to ComboTName_SelectedIndexChanged
Private Sub ComboTName_SelectedIndexChanged(sender As Object, e As EventArgs)
'Cast sender to a ComboBox so we can use the Properties of a ComboBox
Dim Combo = DirectCast(sender, ComboBox)
Dim Name = Combo.Name
Dim N As Integer = GetValueOfN(Name)
Dim Item = Combo.SelectedItem
MessageBox.Show($"The selected item in {Name} is {Item} The number of the combo cox is {N}")
End Sub
Private Function GetValueOfN(ComboName As String) As Integer
Dim NumString = ComboName.Substring(ComboName.IndexOf("1") + 1)
Return CInt(NumString)
End Function
I'm new at visual basic programming and everything was fine until our topic shifted to arrays. I tried to understand it's code using Java. (Example: method are called functions.. .)
My prof has given us an exercise to create a Quiz program that asks the user more than 5 questions (in textbox) with choices (in buttons) and computes the score at the end (All just in one form). If the user click an a button it will tell if it's right or wrong and then proceed to change the question along with the choices.
*Required: - After the user finish the quiz the score will be displayed and there should be a restart button and all the question will be asked again randomly no pattern. - Try to make functions.
I tried searching the web since yesterday and I still have made no progress at my code.
Public Class Form1
Dim questions(5) As String
Dim answers(5) As String
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
'Method/Function for loading the Q&A
loadQsAndAs()
End Sub
Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
Me.Close()
End Sub
Private Sub loadQsAndAs()
'Questions
questions(0) = "What is 1 + 1?"
questions(1) = "Who is the first man to walk on the Moon?"
questions(2) = "What is the name of the main character in the movie: Yes Man! (2007)"
questions(3) = "If I gave you three apples and you ate two, how many is left?"
questions(4) = "What do you want in your final grade?"
questions(5) = "What is the name of the thing(s) that you use whenever you eat?"
'Answers
answers(0) = "2"
answers(1) = "Neil Armstrong"
answers(2) = "Jim Carrey"
answers(3) = "1"
answers(4) = "A 4.0"
answers(5) = "A Spoon and Fork"
TextBox1.Text = setTheQuestion()
Button1.Text = setTheAnswer1()
Button2.Text = setTheAnswer2()
Button3.Text = setTheAnswer3()
Button4.Text = setTheAnswer4()
End Sub
Private Function setTheQuestion() As String
Dim randomValue As New Random
Dim randomQ As String = ""
Dim i As Integer
Dim index As Integer
For i = 0 To 0
index = randomValue.Next(0, questions.Length)
randomQ &= questions(index)
Next
Return randomQ
End Function
Private Function setTheAnswer1() As String
Dim randomValue As New Random
Dim randomAns As String = ""
Dim i As Integer
Dim index As Integer
For i = 0 To 0
index = randomValue.Next(0, answers.Length)
randomAns &= answers(index)
Next
Return randomAns
End Function
Private Function setTheAnswer2() As String
Dim randomValue As New Random
Dim randomAns As String = ""
Dim i As Integer
Dim index As Integer
For i = 0 To 0
index = randomValue.Next(1, answers.Length)
randomAns &= answers(index)
Next
Return randomAns
End Function
Private Function setTheAnswer3() As String
Dim randomValue As New Random
Dim randomAns As String = ""
Dim i As Integer
Dim index As Integer
For i = 0 To 0
index = randomValue.Next(2, answers.Length)
randomAns &= answers(index)
Next
Return randomAns
End Function
Private Function setTheAnswer4() As String
Dim randomValue As New Random
Dim randomAns As String = ""
Dim i As Integer
Dim index As Integer
For i = 0 To 0
index = randomValue.Next(3, answers.Length)
randomAns &= answers(index)
Next
Return randomAns
End Function
Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click
loadQsAndAs()
End Sub
End Class
Public Class Form1
Dim questions As New ArrayList
Dim answers As New ArrayList
Dim dtQAMain As New DataTable
Dim questionsCopy As New ArrayList
Dim alAnsButton As New ArrayList 'arraylist to store all answer button.
Dim totalScore As Integer
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles MyBase.Load
'Method/Function for loading the Q&A
alAnsButton.Add(Button1)
alAnsButton.Add(Button2)
alAnsButton.Add(Button3)
alAnsButton.Add(Button4)
loaddtQA()
loadQsAndAs()
End Sub
Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles Button5.Click
Me.Close()
End Sub
Private Sub loaddtQA()
dtQAMain = New DataTable
dtQAMain.Columns.Add("Q")
dtQAMain.Columns.Add("A")
For i = 0 To 5
questions.Add("")
answers.Add("")
Next
'Questions
questions(0) = "What is 1 + 1?"
questions(1) = "Who is the first man to walk on the Moon?"
questions(2) = "What is the name of the main character in the movie: Yes Man!(2007)"
questions(3) = "If I gave you three apples and you ate two, how many is left?"
questions(4) = "What do you want in your final grade?"
questions(5) = "What is the name of the thing(s) that you use whenever you eat?"
'Answers
answers(0) = "2"
answers(1) = "Neil Armstrong"
answers(2) = "Jim Carrey"
answers(3) = "1"
answers(4) = "A 4.0"
answers(5) = "A Spoon and Fork"
For i = 0 To questions.Count - 1
dtQAMain.Rows.Add(questions(i), answers(i)) 'assign QA in table for scoring purpose later
Next
End Sub
Private Sub loadQsAndAs()
Label1.Visible = False
For i = 0 To alAnsButton.Count - 1
alAnsButton(i).visible = True
Next
questionsCopy = New ArrayList
questionsCopy = questions.Clone 'close a copy so we dont effect the actual question copy when randomize and eliminate asked question from arraylist
TextBox1.Text = setTheQuestion()
setTheAnswer()
End Sub
Private Function setTheQuestion() As String
Dim randomValue As New Random
Dim randomQ As String = ""
Dim index As Integer
If questionsCopy.Count <> 0 Then
index = randomValue.Next(0, questionsCopy.Count - 1)
randomQ = questionsCopy(index)
questionsCopy.RemoveAt(index) 'asked question will be remove.
Else ' questions are finished, show the mark
ShowMark()
End If
Return randomQ
End Function
Private Sub setTheAnswer() 'randonmize the answer and assign to button
If TextBox1.Text = "" Then Exit Sub ' if question finish exit sub
Dim randomValue As New Random
Dim NewIndex As Integer
Dim temp As String
Dim answersCopy As ArrayList = answers.Clone
For n = answersCopy.Count - 1 To 0 Step -1
NewIndex = randomValue.Next(0, n + 1)
' Swap them.
temp = answersCopy(n)
answersCopy(n) = answersCopy(NewIndex)
answersCopy(NewIndex) = temp
Next
Dim AnswerRowCheck As Integer = questions.IndexOf(TextBox1.Text)
Dim ActualAnswer As String = dtQAMain.Rows(AnswerRowCheck).Item("A") 'check actual answer
Dim totalRemove As Integer = 0
For i = answersCopy.Count - 1 To 0 Step -1
If totalRemove = 2 Then Exit For
If answersCopy(i) <> dtQAMain.Rows(AnswerRowCheck).Item("A") Then
answersCopy.RemoveAt(i)
totalRemove += 1
End If
Next 'remove 2 of the selection,since only 4 button for answer selection and should not take out the actual answer
For i = 0 To alAnsButton.Count - 1
alAnsButton(i).text = answersCopy(i)
Next
End Sub
Private Sub ShowMark()
For i = 0 To alAnsButton.Count - 1
alAnsButton(i).text = "" 'clear the text, no more input receive from user.
Next
Label1.Visible = True
Label1.Text = totalScore & " out of 6 are correct."
End Sub
Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click
totalScore = 0
loadQsAndAs() 'refresh question
End Sub
Private Sub Button4_MouseClick(sender As Object, e As MouseEventArgs) Handles Button4.MouseClick, Button3.MouseClick, Button2.MouseClick, Button1.MouseClick
If sender.text = "" Then Exit Sub
Dim AnswerRowCheck As Integer = questions.IndexOf(TextBox1.Text) 'search question number
If dtQAMain.Rows(AnswerRowCheck).Item("A") = sender.text Then 'checking answer
totalScore += 1
End If
TextBox1.Text = setTheQuestion() 'next question
setTheAnswer()
End Sub
End Class
The code had cover most of the necessary comment which include the idea and how it work. Random() and arraylist are the key for this program to function, just pay more attention on it. Good luck.
How about trying this?
Public Class Form1
Dim questions(5) As String
Dim answers(5) As String
Private Sub loadQsAndAs()
'Questions
questions(0) = "What is 1 + 1?"
questions(1) = "Who is the first man to walk on the Moon?"
questions(2) = "What is the name of the main character in the movie: Yes Man! (2007)"
questions(3) = "If I gave you three apples and you ate two, how many is left?"
questions(4) = "What do you want in your final grade?"
questions(5) = "What is the name of the thing(s) that you use whenever you eat?"
'Answers
answers(0) = "2"
answers(1) = "Neil Armstrong"
answers(2) = "Jim Carrey"
answers(3) = "1"
answers(4) = "A 4.0"
answers(5) = "A Spoon and Fork"
Dim random As New Random
Dim indices = { 0, 1, 2, 3, 4, 5 }.OrderBy(Function (n) random.Next()).ToArray()
Dim question = random.Next(questions.Length - 1)
TextBox1.Text = questions(indices(question))
Button1.Text = answers(indices(0))
Button2.Text = answers(indices(1))
Button3.Text = answers(indices(2))
Button4.Text = answers(indices(3))
End Sub
End Class
That's it. Nice and simple. The key trick is creating a randomize indices array to do the lookups into the questions and answers arrays.
Private Dim rnd As Integer
Private Function setTheQuestion() As String
rnd = (CInt(Math.Ceiling(Rnd() * questions.Length)) + 1)
Return questions(rnd)
End Function
Private Function setTheAnswer1() As String
Return answers(rnd)
End Function
I have created a Quiz application in Visual Basic.I have stored the questions in a text file and I'm using streamreader to read the lines.The text file looks like this
If x is the first of five consecutive odd numbers then what is their average ?
x
x+1
x+4
x+3
3
Which of the following number is divisible by 24 ?
76300
78132
80424
81234
3
The first line is the question,the lines 2 to 5 is the options and the 6th line is the answer key and there are more than 100 questions and I should print random questions and its corresponding choices each time I open the application and it should not repeat the same question.Can any one give me a code snippet for this?
Imports System.IO
Imports System.Runtime.InteropServices
Public Class Quiz
Public ques As Integer = 1
Dim Shuffle As Integer = 0
Dim SCORE As Integer = 0
Dim val As Integer = 30
Public anskey As String
Private currentQuestion As Integer
Private listOfQuestions As List(Of Question) = New List(Of Question)
<DllImport("user32.dll", SetLastError:=True, CharSet:=CharSet.Auto)>
Private Shared Function SendMessage(ByVal hWnd As IntPtr, ByVal Msg As UInteger, ByVal wParam As Integer, ByVal lParam As Integer) As IntPtr
End Function
Public Sub Reset_all()
val = 30
SCORE = 0
ProgressBar1.Value = 0
Button3.Hide()
ProgressBar1.Minimum = 0
ProgressBar1.Maximum = 30
Timer1.Enabled = True
Using reader = New System.IO.StreamReader("Quiz.txt")
Dim line = reader.ReadLine()
While (Not String.IsNullOrWhiteSpace(line))
Dim question = New Question
question.Question = line
question.Choice1 = reader.ReadLine()
question.Choice2 = reader.ReadLine()
question.Choice3 = reader.ReadLine()
question.Choice4 = reader.ReadLine()
question.Answer = reader.ReadLine()
listOfQuestions.Add(question)
line = reader.ReadLine()
End While
End Using
If listOfQuestions.Count > 0 Then
LoadQuestion(0)
End If
End Sub
Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
Reset_all()
End Sub
Sub LoadQuestion(questionIndex As Integer)
Dim question = listOfQuestions(questionIndex)
currentQuestion = questionIndex
If listOfQuestions.Count - 1 = currentQuestion Then
End If
With question
Label3.Text = ques
Label1.Text = .Question
RadioButton1.Text = .Choice1
RadioButton2.Text = .Choice2
RadioButton3.Text = .Choice3
RadioButton4.Text = .Choice4
anskey = .Answer
End With
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
If (SCORE > 0) Then
SCORE -= 1
End If
If (currentQuestion > 0) Then
If (ques > 0) Then
ques -= 1
LoadQuestion(currentQuestion - 1)
End If
End If
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
If (anskey = "a" And RadioButton1.Checked = True Or anskey = "b" And RadioButton2.Checked = True Or anskey = "c" And RadioButton3.Checked = True Or anskey = "d" And RadioButton4.Checked = True) Then
SCORE += 1
End If
If (currentQuestion < listOfQuestions.Count - 1) Then
If (ques <= 99) Then
ques += 1
LoadQuestion(currentQuestion + 1)
End If
End If
End Sub
Private Sub Quiz_FormClosing(sender As Object, e As FormClosingEventArgs) Handles MyBase.FormClosing
Dashboard.Show()
Me.Hide()
End Sub
Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick
ProgressBar1.Value += 1
val -= 1
Label2.Text = val & " Sec"
If ProgressBar1.Value = ProgressBar1.Maximum Then
Timer1.Enabled = False
End If
If ProgressBar1.Value > 23 Then
SendMessage(ProgressBar1.Handle, 1040, 2, 0)
Button3.Show()
End If
If ProgressBar1.Value = 30 Then
End If
End Sub
Private Sub SubmitResult()
MsgBox("You have Scored " + SCORE.ToString + " Out of 100")
End Sub
Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
Dim Re As Integer = MsgBox("Are you sure you want to submit?",
vbYesNo, "Submit")
If (Re = 6) Then
SubmitResult()
Try
Me.Close()
Dashboard.Show()
Catch ex As Exception
End Try
End If
End Sub
Private Sub Label1_Click(sender As Object, e As EventArgs) Handles Label1.Click
End Sub
End Class
Public Class Question
Public Property Question As String
Public Property Choice1 As String
Public Property Choice2 As String
Public Property Choice3 As String
Public Property Choice4 As String
Public Property Answer As String
End Class
I would make a class "question" like this:
public Class Question
public questionas String
public answer1 as String
public answer2 as String
public answer3 as String
public answer4 as String
public correctAnswer as integer
public sub new(que as string, a1 as string, a2 as string, a3 as string, a4 as string, answer as integer)
question= que
answer1=a1
answer2=a2
answer3=a3
answer4=a4
correctAnswer=answer
end sub
end Class
Now load all your questions in the programm like this:
Imports System
Imports System.IO
Class MainWindow
private listQuestions as List(Of Question)
Public Sub window_loaded() handles MainWindow.loaded
listQuestions = loadAllQuestions()
End Sub
private function loadAllQuestions() as List(Of Question)
Dim str() As String
Try
' Open the file using a stream reader.
Using sr As New StreamReader("example.txt")
Dim line As String
' Read the stream to a string and write the string to the console.
line = sr.ReadToEnd()
Str = line.Split(vbNewLine)
End Using
Catch e As Exception
Console.WriteLine("The file could not be read:")
Console.WriteLine(e.Message)
End Try
'So now put the questions in your list:
dim list as new List(Of Question)
For i = 0 to str.count - 1
if (i+1) mod 5 = 0 then 'is divible without rest by 6
list.add(new Question(str(i-5), str(i-4), str(i-3), str(i-2), str(i-1), str(i))
end if
next
return list
end sub
'Load a random question:
private sub btNext_click() handles btNext.click()
dim ranQuestion as Question
dim r as new random
ranQuestion = listFragen.item(r.next(0,listQuestions.count))
End Class
Hope i could help you. To prevent that the programm can show the same question again its your job :)
First, I would recommend using the File.ReadAllLines() function to get an array of lines in the text file with questions. Then you can access them easily.
If you observe, the index of the line of the question will be (n - 1) * 6, where n is the question number. Once you get that, the indices of the options are given by:
i + 1
i + 2
i + 3
i + 4
where i = (n - 1) * 6. The answer key is given by:
i + 5
That should get you started. If you get stuck, leave a comment :)
So you would do the first part by:
Dim lines() As String = File.ReadAllLines("<yourQuestions.txt")
Then, you can generate a random number within the required range using:
Dim questionNumber As Integer = Random.Next(1, (lines.Length / 6) + 1)
After that, you can retrieve the question, options and answer key by:
Dim i As Integer = (questionNumber - 1) * 6
Dim question As String = lines(i)
Dim options() As String = {lines(i + 1), lines(i + 2), lines(i + 3), lines(i + 4)}
Dim answerKey As String = lines(Integer.Parse(lines(i + 5)))
You can also consider creating a class Question:
Public Class Question
Public Property Question As String
Public Property Choice1 As String
Public Property Choice2 As String
Public Property Choice3 As String
Public Property Choice4 As String
Public Property Answer As String
Public Sub New(q As String, c1 As String, c2 As String, c3 As String, c4 As String, ans As String)
Question = q
Choice1 = c1
Choice2 = c2
Choice3 = c3
Choice4 = c4
Answer = ans
End Sub
End Class
Then you can assign the properties.
Another alternative (might be better in performance, in fact, I think it should be) would be to use the File.ReadLines() function and use the Take() and Skip() extension methods of IEnumerable<T> (LINQ):
Dim questionNumber As Integer = Random.Next(1, (File.ReadLines("<yourQuestions.txt").Count() / 6) + 1)
Dim blockLines = File.ReadLines("<yourQuestions.txt").Skip((questionNumber - 1) * 6).Take(6)
Dim currentQuestion As New Question(blockLines(0), blockLines(1), blockLines(2), blockLines(3), blockLines(4), blockLines(blockLines(5)))
To start with, load your questions this way:
Dim questions = _
File _
.ReadLines("questions.txt") _
.Select(Function (x, n) New With { .Line = X, .Index = n }) _
.GroupBy(Function (xn) xn.Index \ 6, Function (xn) xn.Line) _
.Select(Function (xs) New Question() With _
{ _
.Question = xs(0), _
.Choice1 = xs(1), _
.Choice2 = xs(2), _
.Choice3 = xs(3), _
.Choice4 = xs(4), _
.Answer = xs(5) _
}) _
.ToArray()
That'll give you an array for your questions:
Next, you need to create a "queue.txt" file that contains the indices of your questions in a random order that you wish to display them in. Here's how to create your queue:
Dim rnd = New Random()
Dim queue = _
Enumerable _
.Range(0, questions.Length) _
.OrderBy(Function (n) rnd.Next()) _
.Select(Function (n) n.ToString()) _
.ToArray()
File.WriteAllLines("queue.txt", queue)
Then when you load your program, you can read this file and choose the next question to ask, and save the file, skipping the first question for next time, like this:
Dim queue = File.ReadAllLines("queue.txt")
Dim questionToAsk As Question = questions(Integer.Parse(queue.First()))
File.WriteAllLines("queue.txt", queue.Skip(1))
It would be up to you to make sure that the file is created when it doesn't exist and to write the code that checks if you've asked all the questions and need to re-create the queue.
Here are the basics of a class that uses XML.
Public Class QuestionAndAnswer
'the container for all questions/answers
Private ReadOnly qa As XElement = <QandA></QandA>
'the container for a question and some number of possible answers
Private ReadOnly ent As XElement = <entry></entry>
'the question
Private ReadOnly aquestion As XElement = <question></question>
'an answer - the c attribute will be "y" for the correct answer
Private ReadOnly ananswer As XElement = <answer c=""></answer>
Private theQA As XElement
Public Sub New()
Me.theQA = New XElement(qa) 'set up
End Sub
Public Sub New(path As String)
Me.theQA = XElement.Load(path)
End Sub
Public Sub Save(path As String)
Me.theQA.Save(path)
End Sub
Private Function AddQuestion(theQuestion As String, correctAnsw As String) As XElement
Dim e As New XElement(ent)
Dim q As New XElement(aquestion)
Dim a As New XElement(ananswer)
q.Value = theQuestion
a.Value = correctAnsw
a.#c = "y"
e.Add(q)
e.Add(a)
Me.theQA.Add(e)
Return e
End Function
Public Function AddQuestion(theQuestion As String, correctAnsw As String,
ans1 As String) As XElement
Dim e As XElement = Me.AddQuestion(theQuestion, correctAnsw)
Dim a As New XElement(ananswer)
a.Value = ans1
e.Add(a)
Return e
End Function
Public Function AddQuestion(theQuestion As String, correctAnsw As String,
ans1 As String, ans2 As String) As XElement
Dim e As XElement = Me.AddQuestion(theQuestion, correctAnsw, ans1)
Dim a As New XElement(ananswer)
a.Value = ans2
e.Add(a)
Return e
End Function
Public Function AddQuestion(theQuestion As String, correctAnsw As String,
ans1 As String, ans2 As String, ans3 As String) As XElement
Dim e As XElement = Me.AddQuestion(theQuestion, correctAnsw, ans1, ans2)
Dim a As New XElement(ananswer)
a.Value = ans3
e.Add(a)
Return e
End Function
Public Function AddQuestion(theQuestion As String, correctAnsw As String,
ans1 As String, ans2 As String, ans3 As String, ans4 As String) As XElement
Dim e As XElement = Me.AddQuestion(theQuestion, correctAnsw, ans1, ans2, ans3)
Dim a As New XElement(ananswer)
a.Value = ans4
e.Add(a)
Return e
End Function
Private Shared prng As New Random
Public LastQuestionAnswer As String
Public Function RandomQuestion() As String
Dim q As XElement = Me.SelectRandomQ
If q IsNot Nothing Then
Dim rv As New System.Text.StringBuilder
rv.AppendLine(q.<question>.Value)
rv.AppendLine()
Dim ie As IEnumerable(Of XElement)
ie = From qa In q.<answer>
Select qa
ie = ie.OrderBy(Function() prng.Next(q.<answer>.Count))
Dim x As Integer = 1
For Each a As XElement In ie
If a.#c = "y" Then
Me.LastQuestionAnswer = x.ToString
End If
rv.AppendFormat("{0}. {1}", x, a.Value)
rv.AppendLine()
x += 1
Next
rv.AppendLine()
Me.LastQuestionAnswer = Me.LastQuestionAnswer.Insert(0, rv.ToString)
Debug.WriteLine(Me.LastQuestionAnswer)
Return rv.ToString
End If
Return ""
End Function
Private Function SelectRandomQ() As XElement
If Me.theQA IsNot Nothing AndAlso Me.theQA.<entry>.Count > 0 Then
Dim ie As IEnumerable(Of XElement)
ie = From ent In Me.theQA.Elements
Where ent.#used <> "y"
Select ent
Dim rv As XElement = ie(prng.Next(ie.Count))
rv.#used = "y"
Return rv
End If
Return Nothing
End Function
End Class
A form with a richtextbox and a button shows it
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim foo As New QuestionAndAnswer
foo.RandomQuestion()
foo.AddQuestion("Which Vietnam War film directed by Francis Ford Coppola followed a screenplay based on famous adventure story Heart of Darkness?",
"Apocalypse Now",
"Good Morning Vietnam",
"Born on the Fourth of July",
"Band of Brothers")
foo.AddQuestion("What was the name of the baseball pitcher that hit a bird with a pitch during a 2001 Spring Training game?",
"Randy Johnson",
"Mike Mussina",
"Roger Clemens",
"Greg Maddux",
"Johan Santana")
foo.AddQuestion("The third largest desert in the world is the Sahara, what is the first?",
"Antarctic",
"Gobi",
"Sonoran")
foo.AddQuestion("How many US presidents have died while in office?",
"8",
"6",
"7")
foo.AddQuestion("If x is the first of five consecutive odd numbers > 0, then what is their average?",
"x + 4",
"x",
"x + 1",
"x + 3")
Dim qa As New System.Text.StringBuilder
foo.RandomQuestion()
qa.AppendLine(foo.LastQuestionAnswer)
qa.AppendLine()
foo.RandomQuestion()
qa.AppendLine(foo.LastQuestionAnswer)
qa.AppendLine()
foo.RandomQuestion()
qa.AppendLine(foo.LastQuestionAnswer)
RichTextBox1.Text = qa.ToString
End Sub
i have datagridview with 4 columns
[Nam] , [ID] , [Shuru] , [Payan]
second column ([ID]) is hidden and is used to gather some details about the data.
this is the Load code :
Private Sub SalMali_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Me.DGV_SalMaliTableAdapter.Fill(Me.FDBDataSet.DGV_SalMali)
End Sub
which retrieves everything in DGV_SalMali table.
i know that datagridview automatically selects first row after a fill so i put a function in the Selection Change to retrieve data. here is the code :
Private Sub DGV_SalMaliDataGridView_SelectionChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles DGV_SalMaliDataGridView.SelectionChanged
refreshDT()
End Sub
Public Sub refreshDT()
Dim cnt As Integer = DGV_SalMaliDataGridView.Rows.Count
If cnt = 0 Then
GoTo line
End If
unlockAll()
Dim sel As String = DGV_SalMaliDataGridView.SelectedRows(0).Cells(1).Value
Dim dt As New DataTable
dt = SalMaliTA.GetData_SalMali_B_ID(sel)
Dim dtr As DataRow = dt.Rows(0)
TextBox1.Text = dtr.Item(4)
MaskedTextBox1.Text = mc.MtoS(dtr.Item(1))
MaskedTextBox2.Text = mc.MtoS(dtr.Item(2))
CheckBox1.Checked = dtr.Item(3)
Exit Sub
line:
lockAll()
End Sub
but when I call refreshDT() the selection doesn't work anymore. it throws an error on line 8 of refreshDT()
sub { exactly here : Dim sel As String = DGV_SalMaliDataGridView.SelectedRows(0).Cells(1).Value }
Thrown: "Index was out of range. Must be non-negative and less than
the size of the collection."
(System.ArgumentOutOfRangeException) Exception Message = "Index was
out of range. Must be non-negative and less than the size of the
collection.", Exception Type = "System.ArgumentOutOfRangeException"
datagridview has rows and i dont know what the problem is.
thanks for help.
you're currently checking if there are any rows but not any selected rows:
Public Sub refreshDT()
Dim cnt As Integer = DGV_SalMaliDataGridView.Rows.Count
If cnt = 0 Then
lockAll()
Exit Sub
End If
If DGV_SalMaliDataGridView.SelectedRows.Count = 0 Then
DGV_SalMaliDataGridView.Rows(0).Selected = true
End If
unlockAll()
Dim sel As String = DGV_SalMaliDataGridView.SelectedRows(0).Cells(1).Value
Dim dt As New DataTable
dt = SalMaliTA.GetData_SalMali_B_ID(sel)
Dim dtr As DataRow = dt.Rows(0)
TextBox1.Text = dtr.Item(4)
MaskedTextBox1.Text = mc.MtoS(dtr.Item(1))
MaskedTextBox2.Text = mc.MtoS(dtr.Item(2))
CheckBox1.Checked = dtr.Item(3)
End Sub
How would one select item in listview (first column) that is most similar to string value from e.g. label or textbox.
Listview is populated with this code :
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
ListView1.Items.Clear()
ListView1.View = System.Windows.Forms.View.Details
ListView1.Columns.Add("COL1", 100, HorizontalAlignment.Left) 'KONTO
ListView1.Columns.Add("COL2", 140, HorizontalAlignment.Left) 'NAZIV
Dim FilePath As String = "W:\GLAVNI\KOR14\"
Dim DBF_File As String = "MATIKGL"
Dim ColName As String = "KONTO"
'Dim naz As String
Using con As New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & FilePath & _
" ;Extended Properties=dBASE IV")
con.Open()
Using cmd As New OleDbCommand("SELECT * FROM MATIKGL ORDER BY KONTO, NAZIV", con)
Using reader As OleDbDataReader = cmd.ExecuteReader()
If reader.HasRows Then
While (reader.Read())
Me.ListView1.Items.Add(reader("KONTO"))
'ListView1.Items(i).SubItems.Add(rdr.Item("YourColumnName").ToString)
'BELOW SELECTS ALL ITEMS THAT STARTS WITH 2020-
For i = 0 To ListView1.Items.Count - 1
If ListView1.Items(i).ToString.Contains("2020-") Then
Else
ListView1.Items.Remove(ListView1.Items(i))
End If
Next
End While
Else
End If
End Using
End Using
con.Close()
End Using
End Sub
I have one textbox and a button.
Textual input from textbox should be compared with all items in listview and closest should be selected. One more thing : All items are sorted alphabetically
Button code is :
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
ListView1.MultiSelect = False
ListView1.FullRowSelect = True
Dim checkInt As Integer = FindItem(ListView1, "2020-" & TextBox1.Text)'this one is changed since all items starts with "2020-"& UCASE TEXT
If checkInt <> -1 Then
ListView1.Items(checkInt).Selected = True
ListView1.Focus()
Else
Label1.Text = "Search string not found"
End If
End Sub
UPDATED CODE
Dim checkInt As Integer = FindItem(ListView1, "2020-" & TextBox3.Text)
If checkInt <> -1 Then
TextBox4.Focus()
Else
Label14.Text = "NEMA"
On Error GoTo ext
Dim li As ListViewItem
ListView1.SelectedItems.Clear()
ListView1.HideSelection = False
li = ListView1.FindItemWithText("2020-" & UCase(TextBox3.Text))
If Not (li Is Nothing) Then
Me.ListView1.Focus()
li.Selected = True
li.EnsureVisible()
ElseIf li Is Nothing Then
li = ListView1.FindItemWithText("2020-" & Strings.Left(TextBox3.Text, 1))
Me.ListView1.Focus()
li.Selected = True
li.EnsureVisible()
Else
End If
Exit Sub
ext:
TextBox3.Text = ""
TextBox3.Focus()
Label14.Text = "String not found"
End If
This one works.
I know it's not the best solution but it's working.
Could fixed this without your help, thank you Phillip Trelford
Define a function to score two strings for closeness then use LINQ to find the lowest score, i.,e.
' Example score function
Function Score(a As String, b As String) As Integer
Dim index = 0
While index < a.Length And index < b.Length
Dim diff = Math.Abs(AscW(a(index)) - AscW(b(index)))
If diff <> 0 Then Return diff
index += 1
End While
Return Math.Abs(a.Length - b.Length)
End Function
Function Closest(searchWord As String, words As String()) As String
Dim ordered =
From w In words
Select Word = w, Score = Score(w, searchWord)
Order By Score
Return ordered.First().Word
End Function
Sub Main()
Dim words = {"Alpha", "Apple", "Ask"}
Dim searchWord = "Ann"
Dim word = Closest(searchWord, words)
Console.WriteLine(word)
End Sub
Update
To select the value in a WinForms ListView, you need to do roughly this:
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
ListView1.MultiSelect = False
ListView1.FullRowSelect = True
Dim prefix = "2020-"
' Extract items from Listview
Dim items = New List(Of String)()
For Each item In ListView1.Items
items.Add(item)
Next
Dim words = items.ToArray()
Dim searchWord = TextBox1.Text
Dim resultWord = Closest(searchWord, words)
'this one is changed since all items starts with "2020-"& UCASE TEXT
Dim checkInt As Integer = FindItem(ListView1, prefix & resultWord)
If checkInt <> -1 Then
ListView1.Items(checkInt).Selected = True
ListView1.Focus()
Else
Label1.Text = "Search string not found"
End If
End Sub