How can I join the accid string values from the For Next loop (below) into one single string?
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim accid As String
Dim iLast As Integer
iLast = trv.Nodes.Count
Dim p As Integer = 0
For p = 0 To iLast - 1
If TrV.Nodes(p).Checked = True Then
accid = Strings.Left(TrV.Nodes(p).Text, 9)
MsgBox(accid)
End If
Next
End Sub
This gives me a separate output of string "accid"
I want this output: "accid1,accid2,accid3"
Thanks for supporting!
You need to build your string inside the loop, and then do the MsgBox outside the loop. Something like this should work:
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim accid As String
Dim iLast As Integer
iLast = trv.Nodes.Count
Dim p As Integer = 0
For p = 0 To iLast - 1
If TrV.Nodes(p).Checked = True Then
accid = accid & Strings.Left(TrV.Nodes(p).Text, 9) & "," 'notice the change here
End If
Next
accid = accid.Remove(accid.Length - 1, 1)
MsgBox(accid)
End Sub
This could be done with very few lines of code using Linq and String.Join.
Dim texts = TrV.Nodes.Cast(Of TreeNode)().
Where(Function(n) n.Checked).
Select(Function(c) Strings.Left(c.Text,9))
Dim result = String.Join(",", texts)
Related
I cannot get my code below to work correctly, in fact I want to press a back button in order to go up the lines one by one of a text file then I cut the chain into 3 parts.
Dim LinesOfText() As String = System.IO.File.ReadAllLines("c:\essai.librairie", Encoding.UTF8)
For line As Integer = LinesOfText.Length - 1 To 0 Step -1
Dim currentLine As String = LinesOfText(line)
Dim value As String = currentLine
Dim startIndex As Integer = 0
Dim length As Integer = 17
Dim substring As String = value.Substring(startIndex, length)
Dim subs As String = value.Substring(17, 90)
Dim subst As String = value.Substring(107, 120)
TextBox1.Text = substring
TextBox2.Text = subs
TextBox3.Text = subst
Next
If you store the lines and a line counter so that they are in scope where needed, you can do it like this:
Imports System.IO
Public Class Form1
Dim lines As String()
Dim currentLine As Integer = -1
Sub LoadData(filename As String)
lines = File.ReadAllLines(filename)
currentLine = lines.Length - 1
End Sub
Sub ShowCurrentLine()
If currentLine >= 0 Then
TextBox1.Text = lines(currentLine).Substring(0, 3)
TextBox2.Text = lines(currentLine).Substring(4, 3)
TextBox3.Text = lines(currentLine).Substring(8, 3)
lblLineNo.Text = (currentLine + 1) & "/" & lines.Length
Else
TextBox1.Clear()
TextBox2.Clear()
TextBox3.Clear()
lblLineNo.Text = "-"
End If
End Sub
Private Sub bnNext_Click(sender As Object, e As EventArgs) Handles bnNext.Click
If currentLine < lines.Length - 1 Then
currentLine += 1
ShowCurrentLine()
End If
End Sub
Private Sub bnPrev_Click(sender As Object, e As EventArgs) Handles bnPrev.Click
If currentLine > 0 Then
currentLine -= 1
ShowCurrentLine()
End If
End Sub
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
LoadData("C:\temp\SO67209265.txt")
ShowCurrentLine()
End Sub
End Class
You will need to set the substring parameters for your data—I just used a small text file—and the filename to be loaded.
The label lblLineNo is used to show the current line number, starting at 1.
getting the logic of counting is easy but in practice it gets hard sometimes.
Now I've a list with many items on it. how to count those items if there were repeated and i want to convert that to a number using the FOR loop since i know how many items in the list.
I tried some codes but i did not succeed
'''''''''''''''
' VB 2015
''''''''''''
Public Class Form1
Private Sub lstWinners_List_SelectedIndexChanged(sender As Object, e As EventArgs) Handles lstWinners_List.SelectedIndexChanged
If lstWinners_List.SelectedIndex <> -1 Then
Dim count As Integer = 0
Dim strselection As String = lstWinners_List.Items(lstWinners_List.SelectedIndex).ToString
For i As Integer = 0 To lstWinners_List.Items.Count - 1
If lstWinners_List.Items(i) = strselection Then
count = count + 1
End If
Next
lblOutput.Text = count.ToString
End If
End Sub
End Class
for EX:
i wanna count the word "michigan " how many times repeated in the list by just clicking on it ?
Here's an example using Jim Hewitt's comment:
Private Sub lstWinners_List_SelectedIndexChanged(sender As Object, e As EventArgs) Handles lstWinners_List.SelectedIndexChanged
If lstWinners_List.SelectedIndex <> -1 Then
Dim selection As String = lstWinners_List.Items(lstWinners_List.SelectedIndex).ToString
Dim wins As Integer = (From team As String In lstWinners_List.Items Where team.Equals(selection)).Count
lblOutput.Text = wins.ToString
End If
End Sub
Edit
Here's an equivalent, manual, indexed for loop:
Private Sub lstWinners_List_SelectedIndexChanged(sender As Object, e As EventArgs) Handles lstWinners_List.SelectedIndexChanged
If lstWinners_List.SelectedIndex <> -1 Then
Dim count As Integer = 0
Dim selection As String = lstWinners_List.Items(lstWinners_List.SelectedIndex).ToString
For i As Integer = 0 To lstWinners_List.Items.Count - 1
If lstWinners_List.Items(i) = selection Then
count = count + 1
End If
Next
lblOutput.Text = count.ToString
End If
End Sub
Dim count As Integer = 0
For Each n As String In ListBox1.Items
If n = "red" Then
count += 1
End If
Next
lblOutput.Text(count)
something like this do you mean?
For an assigment my teacher is asking that we read from a file to find the characters of our name and place them at a label at the top of the form.
here is my code:
Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
searchFile = File.OpenText("AcademicEthicsandIntegrityStatement.txt")
Dim s As String = searchFile.ReadToEnd
Dim b As String = s.IndexOf("b"c)
Dim r As Integer = s.IndexOf("r"c)
Dim i As Integer = s.IndexOf("i"c)
Dim a As Integer = s.IndexOf("a"c)
Dim n As Integer = s.IndexOf("n"c)
Dim ec As Integer = s.IndexOf("e"c)
Dim bRead = GetChar(s, b)
Dim rRead = GetChar(s, r)
Dim iRead = GetChar(s, i)
Dim aRead = GetChar(s, a)
Dim nRead = GetChar(s, n)
Dim ecRead = GetChar(s, ec)
lblName.Text = bRead + rRead + iRead + aRead + nRead + nRead + ecRead
End Sub
The text that is reading into my lbl is "gmcaad" instead of "brianne"
Im sure that I am missing something here or there is a much easier way to do this. Any help is appreciated.
IndexOf returns a zero-based index.
GetChar accepts a one-based index.
For consistency,
if you want to use IndexOf, then use direct indexing instead of GetChar:
Dim bRead = s(b)
Dim rRead = s(r)
if you want to use GetChar, then use InStr instead of IndexOf that also returns one-based values.
Short Answer...case sensitive:
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles Me.Load
With File.ReadAllText("AcademicEthicsandIntegrityStatement.txt")
For Each C As Char In "Brianne".ToCharArray
' Note this is case-sensitive because it uses a binary comparison
Dim Index As Integer = .IndexOf(C)
If Index >= 0 Then lblName.Text &= .Substring(Index, 1)
Next
End With
End Sub
... and non-case sensitive:
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles Me.Load
With File.ReadAllText("AcademicEthicsandIntegrityStatement.txt")
For Each C As Char In "Brianne".ToCharArray
' Note this is not case-sensitive
Dim Index As Integer = .IndexOf(C.ToString, StringComparison.InvariantCultureIgnoreCase)
If Index >= 0 Then lblName.Text &= .Substring(Index, 1)
Next
End With
End Sub
Hi I'm created a program for a project and I've now started running some tests and the score for the user isn't being calculated correctly and I believe that it can't compare the answer given to the correct answer. I'm very confused and need any help that can be given. My code looks like this, any confusing parts and I'll try and explain.
Imports System.IO
Public Class QuestionScreen
Dim score As Integer = 0
Dim count As Integer
Dim Difficulty_ext As String
Dim questions, answers As New List(Of String)()
Private i As Integer
Sub ReadFile()
If Main.Diff_DDown.Text = "Easy" Then
Difficulty_ext = "questions - Easy"
ElseIf Main.Diff_DDown.Text = "Medium" Then
Difficulty_ext = "questions - Medium"
Else
Difficulty_ext = "questions - Difficult"
End If
Randomize()
Dim countline = File.ReadAllLines("c:\Users\Alice\Desktop\programme files\" & Difficulty_ext & ".txt").Length
Dim numline As Integer
Dim values() As String
Using sr As New StreamReader("c:\Users\Alice\Desktop\programme files\" & Difficulty_ext & ".txt")
While Not sr.EndOfStream
values = sr.ReadLine().Split(","c)
questions.Add(values(0))
answers.Add(values(1))
End While
End Using
numline = Int(Rnd() * countline)
For i As Integer = 0 To numline
Question.Text = questions(i)
Act_ANS.Text = answers(i)
Next
End Sub
Private Sub Pass_Btn_Click(sender As Object, e As EventArgs) Handles Pass_Btn.Click
If count < 10 Then
Call ReadFile()
count = count + 1
Ans_TxtBx.Text = ""
Hid_Score.Text = score
Else
ResultsScreen.Show()
Me.Hide()
End If
End Sub
Public Sub Submit_Btn_Click(sender As Object, e As EventArgs) Handles Submit_Btn.Click
If count < 10 Then
Call ReadFile()
count = count + 1
If Ans_TxtBx.Text = answers(i) Then
score = score + 1
End If
Hid_Score.Text = score
Else
ResultsScreen.Show()
Me.Hide()
count = 0
End If
Ans_TxtBx.Text = ""
End Sub
Private Sub QuestionScreen_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Call ReadFile()
End Sub
End Class
OK..... Try this, I have debugged your code trying to leave it pretty much as you had it, there were a number of problems, nothing major just a few lines of code in the wrong place....
Imports System.IO
Public Class Form1
Dim score As Integer = 0
Dim count As Integer
Dim Difficulty_ext As String
Dim questions, answers As New List(Of String)()
Private i As Integer
Sub ReadFile()
If Diff_DDown.Text = "Easy" Then
Difficulty_ext = "questions - Easy"
ElseIf Diff_DDown.Text = "Medium" Then
Difficulty_ext = "questions - Medium"
Else
Difficulty_ext = "questions - Difficult"
End If
Randomize()
Try
Dim countline = File.ReadAllLines("c:\Users\Alice\Desktop\programme files\" & Difficulty_ext & ".txt").Length
Dim numline As Integer
Dim values() As String
' clear the list of questions and answers
answers.Clear()
questions.Clear()
'''''''''''''''''''''''''''''''''''''''''
Using sr As New StreamReader("c:\Users\Alice\Desktop\programme files\" & Difficulty_ext & ".txt")
While Not sr.EndOfStream
values = sr.ReadLine().Split(","c)
questions.Add(values(0))
answers.Add(values(1))
End While
End Using
numline = Int(Rnd() * countline)
For i = 0 To numline
Question.Text = questions(i)
Act_ANS.Text = answers(i)
Next
Catch ex As Exception
End Try
End Sub
Private Sub Pass_Btn_Click(sender As Object, e As EventArgs) Handles Pass_Btn.Click
If count < 10 Then
count = count + 1
Ans_TxtBx.Text = ""
Hid_Score.Text = score
Else
ResultsScreen.Show()
Me.Hide()
End If
Call ReadFile() ' move this to the bottom
End Sub
Public Sub Submit_Btn_Click(sender As Object, e As EventArgs) Handles Submit_Btn.Click
If count < 10 Then
count = count + 1
If Ans_TxtBx.Text = answers(i - 1) Then ' need to subtract 1 here
score = score + 1
End If
Hid_Score.Text = score
Else
ResultsScreen.Show()
Me.Hide()
count = 0
End If
Ans_TxtBx.Text = ""
Call ReadFile() ' move this to the bottom
End Sub
Private Sub QuestionScreen_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Call ReadFile()
End Sub
End Class
so i made this but when i enter a string it would only detect one character
and it wont convert the entered string to lower case too
Dim readme, readme2 As String
Dim j, i As Integer
Dim Compare As Integer
readme = TextBox1.Text
readme2 = TextBox2.Text
readme.ToLower.Substring(i, readme.Length)
readme2.ToLower.Substring(j, readme2.Length)
For i = 0 To readme.Length
For j = 0 To readme2.Length
If readme = readme2 Then
Compare = +1
End If
Next
Next
Label4.Text = Compare`enter code here`
Strings are immutable. You cannot apply a method to a string and expects that string to change in response to the inner operations of that method.
You need to reassign the result of the operation to the same string that you have used to call the method
readme = readme.ToLower()
readme2 = readme2.ToLower()
The second part of your question is more confused, are you trying to count the number of equal chars in the same position?
In that case your loop should be
Dim maxLenToCheck = Math.Min(readme.Length, readme2.Length)
For i = 0 To maxLenToCheck - 1
If readme(i) = readme2(i) Then
Compare += 1
End If
Next
In that loop you set always the Compare to 1, the correct syntax to increment the Compare variable is
Compare += 1
Following your comment below, then I presume that your loop should be written as
Dim Compare = 0
For i = 0 To readme.Length - 1
for j = 0 to readme2.Length -1
If readme(i) = readme2(j) AndAlso _
Not Char.IsWhiteSpace(readme(i)) Then
Compare += 1
End If
Next
Next
Based on the comments in the solution by Steve, the author wants to know the count of letters occurring in both strings, ignoring case and white spaces.
By my count, however, the solution should be 21, not 20. Here is a solution using LINQ that also gives visual feedback on where those letters are located:
Public Class Form1
Private Class LetterCount
Public Letter As Char
Public Count As Integer
Public Overrides Function ToString() As String
Return Letter & " : " & Count
End Function
End Class
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
TextBox1.Text = "This is a Test"
TextBox2.Text = "This should be tryed before"
RichTextBox1.ReadOnly = True
RichTextBox1.Font = New Font("MS Courier", 14) ' monospaced font
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
RichTextBox1.Text = TextBox1.Text & vbCrLf & TextBox2.Text & vbCrLf
Dim charsA As New List(Of Char)(TextBox1.Text.ToLower.ToCharArray.Where(Function(x) Not Char.IsWhiteSpace(x)))
Dim charsB As New List(Of Char)(TextBox2.Text.ToLower.ToCharArray.Where(Function(x) Not Char.IsWhiteSpace(x)))
Dim DistinctCommonLetters = (From A In charsA, B In charsB Where A = B Select A).Distinct
Dim DistinctCounts =
From Letter In DistinctCommonLetters, C In charsA.Concat(charsB)
Where C = Letter
Group By Letter Into Group
Select New LetterCount With {.Letter = Letter, .Count = Group.Count}
Dim TotalMatches = DistinctCounts.Sum(Function(x) x.Count)
ListBox1.DataSource = DistinctCounts.ToList
Label1.Text = "TotalMatches: " & TotalMatches
End Sub
Private Sub ListBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ListBox1.SelectedIndexChanged
Dim LC As LetterCount = ListBox1.SelectedItem
RichTextBox1.SelectAll()
RichTextBox1.SelectionColor = Color.Black
Dim index As Integer = RichTextBox1.Find(LC.Letter, 0, RichTextBoxFinds.None)
While index <> -1
RichTextBox1.Select(index, 1)
RichTextBox1.SelectionColor = Color.Red
index = RichTextBox1.Find(LC.Letter, index + 1, RichTextBoxFinds.None)
End While
End Sub
End Class