I am getting an error when I execute this button event: here is my code:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles Button1.Click
Try
' get the details of the item
Dim R As Your_pharmacy.POSDS.ItemsRow = Button1.Tag
' next search for the barcode in the datagridview
Dim I As Integer
Dim ItemLoc As Integer = -1
For I = 0 To DGV1.Rows.Count - 1
If R.barcodeNumber = DGV1.Rows(I).Cells(0).Value Then
' item found
ItemLoc = I
Exit For
End If
Next
' if item is not found, add it
If ItemLoc = -1 Then
DGV1.Rows.Add(R.barcodeNumber, R.ItemName, R.BuyPrice, R.SellPrice, 1, R.SellPrice)
Else
' if item is already there increase its count
Dim ItemCount As Long = DGV1.Rows(ItemLoc).Cells(4).Value
ItemCount += 1
Dim NewPrice As Decimal = R.SellPrice * ItemCount
DGV1.Rows(ItemLoc).Cells(4).Value = ItemCount
DGV1.Rows(ItemLoc).Cells(5).Value = NewPrice
End If
' next clear textbox1 and set focus to it
TextBox1.Text = ""
TextBox1.Focus()
' compute the total for the recipt
Dim Sum As Decimal = 1
For I = 0 To DGV1.Rows.Count - 1
Sum += DGV1.Rows(I).Cells(5).Value 'here the error happens
Next
TextBox4.Text = Sum
Catch ex As Exception
MsgBox(ex.Message, MsgBoxStyle.Critical Or MsgBoxStyle.OkOnly, "Error")
End Try
End Sub
The error details:
error: index was out of range.must be non-negative and less than the
size of the collection. parameter name: index vb.net
DGV1 must have fewer cells than 5. When the error occurs, use a breakpoint and the debug watch window to see how many cells there are in DVG1(I). Maybe the first one is created with zero cells?
Related
I am a new programmer learning Visual Basic.
Right now, I'm working on a project about a softball scoreboard. I have been working on this project for a bit, and I am confused on 1 thing.
The thing I am confused on is that I put in a messagebox that said invalid input for negative numbers, but it does not delete it from lstScores and even though the message box appears it still counts as a inning input.
If runs < 0 Then
MessageBox.Show(VALID_MESSAGE)
This is the code:
Public Class frmSoftballScoreboard
Const VALID_MESSAGE As String = "Enter valid runs value"
Const ONLY_MESSAGE As String = "Only seven innings are allowed"
'Declaring array
Dim scores(6) As Double
'declaring variables
Dim runs As String
Dim runningScore As Integer = 0
Dim i As Integer = 0
Dim out As Double
'page load event
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
lstScores.Items.Add("Runs : Running Score")
End Sub
'Enter score button
Private Sub btnScore_Click(sender As Object, e As EventArgs) Handles btnScore.Click
If i < scores.Length Then
'display inputbox to the user
runs = InputBox("Enter score for " & (i + 1) & " innings", "Score")
'if runs is entered
If runs <> "" Then
'parse the value of runs
If (Double.TryParse(runs, out)) Then
'parse the runs and add it to the array scores()
scores(i) = Double.Parse(runs)
runningScore += scores(i)
'add the rainfall value to the listbox along with month name
lstScores.Items.Add(scores(i) & " :" & runningScore)
'increment the value of i
i = i + 1
Else
'display error message
MessageBox.Show(VALID_MESSAGE)
lblTotal.Text = ""
End If
Else
'if runs is empty then display error message
MessageBox.Show("Enter runs for " & i & "innings")
End If
Else
MessageBox.Show(ONLY_MESSAGE)
End If
If runs < 0 Then
MessageBox.Show(VALID_MESSAGE)
End If
'calculate total runs And display on the lable
If scores(6) = 7 Then
lblTotal.Text = String.Format("final score is {0}", scores.Sum())
End If
End Sub
'Clear Menu click
Private Sub ClearToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles mnuClear.Click
lstScores.Items.Clear()
lblTotal.Text = ""
'reset i to 0
i = 0
End Sub
'Exit Menu click
Private Sub ExitToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles mnuExit.Click
'close application
Application.Exit()
End Sub
End Class
I would really appreciate it if you could help. Thank you.
Private Sub btnScore_Click(sender As Object, e As EventArgs) Handles btnScore.Click
If i < scores.Length Then
'display inputbox to the user
runs = InputBox("Enter score for " & (i + 1) & " innings", "Score")
'if runs is entered
If runs < 0 Then
MessageBox.Show(VALID_MESSAGE)
Exit Sub
ElseIf runs <> "" Then
'parse the value of runs
If (Double.TryParse(runs, out)) Then
'parse the runs and add it to the array scores()
scores(i) = Double.Parse(runs)
runningScore += scores(i)
'add the rainfall value to the listbox along with month name
lstScores.Items.Add(scores(i) & " :" & runningScore)
'increment the value of i
i = i + 1
Else
'display error message
MessageBox.Show(VALID_MESSAGE)
lblTotal.Text = ""
End If
Else
'if runs is empty then display error message
MessageBox.Show("Enter runs for " & i & "innings")
End If
Else
MessageBox.Show(ONLY_MESSAGE)
End If
If runs < 0 Then
MessageBox.Show(VALID_MESSAGE)
End If
'calculate total runs And display on the lable
If scores(6) = 7 Then
lblTotal.Text = String.Format("final score is {0}", scores.Sum())
End If
End Sub
This is the reason why if you input invalid data it will add into lstScores, because your If statement.. is in bottom of your code, although is not recommend where you put the If else statement... Remember reading of the code is start in top to bottom.
Your first If statement is like this. If runs <> "" then ...., of course if you type the -1 value in the Input Text the Boolean will result to true, If -1 <> "" = true, then it will proceed to the statement which is
If (Double.TryParse(runs, out)) Then
'parse the runs and add it to the array scores()
scores(i) = Double.Parse(runs)
runningScore += scores(i)
'add the rainfall value to the listbox along with month name
lstScores.Items.Add(scores(i) & " :" & runningScore)
'increment the value of i
i = i + 1
This is the line of code even the value is invalid or not it still adding value in the lstScores, lstScores.Items.Add(scores(i) & " :" & runningScore)
Now after that statement you will receive a message which is :
Enter valid runs value
If runs < 0 Then
MessageBox.Show(VALID_MESSAGE)
End If
That code is the reason why you receiving the message. If you input -1 of course the result of boolean is true, why? -1 is lessthan to 0 which is true.
The thing i do is, I've insert If statement.. above, which is If runs < 0 then .... and also Exit Sub to instantly end the statement. If you input -1 to Input Text the result is something like this, if runs(-1) lessthan to 0 the Boolean result is true then it will proceed to statement which is the Message and Exit Sub.
Try my code above, and also use Breakpoints.. Hope this helps..
I have problem in my project with VB 2008.
I have 5 textbox that only contains numeric. From all of inputted value will be shown in Listbox and sort by ascending.
I use this code below
Private Sub InptBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles InptBtn.Click
Dim List As New List(Of Double)
Dim chkList As New Integer
Dim getData() As String = {Inpt1.Text, Inpt2.Text, Inpt3.Text, Inpt4.Text, Inpt5.Text, Inpt6.Text}
' empty check
For idx As Integer = 0 To getData.Length - 1
chkList += getData(idx).Trim.Length
Next
If chkList = 0 Then
MessageBox.Show("EMPTY！", "WARNING!", MessageBoxButtons.OK, MessageBoxIcon.Warning)
Return
End If
' numeric check
Dim d1 As Double = 0
For idx As Integer = 0 To getData.Length - 1
If Double.TryParse(getData(idx), d1) Then
List.Add(d1)
End If
Next
If List.Count = 0 Then
MessageBox.Show("Please fill with number！", "WARNING!", MessageBoxButtons.OK, MessageBoxIcon.Warning)
Return
End If
List.Sort()
ListBox.DataSource = List
End Sub
It's work! But I have 1 problem.
If I try to input
0.0000000000001 or 0.00000000000000000002
It's shown like
1E-13 or 2E-20
I tried to use ToString method and change List type by String after sorting like code below, but it doesn't work.
For idx As Integer = 0 To getData.Length - 1
If Double.TryParse(getData(idx), d1) Then
List.Add(d1.ToString())
End If
Next
Could I show all inputted value as I inputted with Decimal type? Or there's some way to shown it with other type?
Shown like below in Listbox:
0.0000000000001 or 0.00000000000000000002
Thank you so much!
Can you try this ?
For idx As Integer = 0 To getData.Length - 1
If Double.TryParse(getData(idx), d1) Then
List.Add(FormatNumber(d1.ToString, 20))
End If
Next
This is the error I am getting
System.InvalidOperationException: 'List that this enumerator is bound to has been modified. An enumerator can only be used if the list does not change.'
I have a Listbox that is databound The list of items are stored days table the saved value is stored in a record table. The List is a Comma Separated List E.G: 1,2,3,4,5
Would equate to Items with values of 1 -5 being selected on load.
This is the save Routine which Works perfectly
Private Sub ListBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ListBox1.Leave
Dim listboxItems As New List(Of String)
For Each row As DataRowView In ListBox1.SelectedItems
listboxItems.Add(row("IDNum"))
Next row
selectLoad = True
lblDays.Text = String.Join(",", listboxItems.ToArray())
End Sub
This is Routine Which is Throwing the error.
Private Sub BGWLoadData_RunWorkerCompleted(sender As Object, e As System.ComponentModel.RunWorkerCompletedEventArgs) Handles BGWLoadData.RunWorkerCompleted
Dim TextBoxStrings() As String = {""}
Try
Dim TempStr() As String = lblDays.Text.Split(",")
ReDim TextBoxStrings(TempStr.Count - 1)
TextBoxStrings = TempStr
Catch ex As Exception
End Try
Dim TextBoxDoubles(TextBoxStrings.Count - 1) As Double
For a As Integer = 0 To TextBoxStrings.Count - 1
Try
TextBoxDoubles(a) = TextBoxStrings(a)
Catch ex As Exception
TextBoxDoubles(a) = 0
End Try
Next
Do While DaysBound = False
Application.DoEvents()
Loop
ListBox1.SelectedItems.Clear()
Dim TempIndex As Integer = 0
For Each row As DataRowView In ListBox1.Items
For a As Integer = 0 To TextBoxDoubles.Count - 1
If row("IDNum") = TextBoxDoubles(a) Then
ListBox1.SetSelected(TempIndex, True)
End If
Next
TempIndex = TempIndex + 1
Next row
End Sub
What am I doing wrong or what can be done to make the code more efficient.
Edit:
Error Occurs at Next Row.
Also telling me I have done something wrong isn't helpful I know something is Wrong because I am getting errors. I am asking for is how to fix this with a code snippet or something.
This Has been Solved by Adding a second arrary
If selectLoad = False Then
' convert CSV of IDNums of selected items in listbox into string array
Dim TextBoxStrings() As String = {""}
Try
Dim TempStr() As String = lblDays.Text.Split(",")
ReDim TextBoxStrings(TempStr.Count - 1)
TextBoxStrings = TempStr
Catch ex As Exception
End Try
' convert string array to double array
Dim TextBoxDoubles(TextBoxStrings.Count - 1) As Double
For a As Integer = 0 To TextBoxStrings.Count - 1
Try
TextBoxDoubles(a) = TextBoxStrings(a)
Catch ex As Exception
TextBoxDoubles(a) = -1
End Try
Next
' load underlying IDNums into temporary array
Dim TempIndex As Integer = 0
Dim TempIDNums(ListBox1.Items.Count - 1) As Integer
For Each row As DataRowView In ListBox1.Items
TempIDNums(TempIndex) = row("IDNum")
TempIndex = TempIndex + 1
Next row
' if any of the underlying IDNums are found in the CSV, select that item in the listbox
ListBox1.SelectedItems.Clear()
For ListItemCounter As Integer = 0 To TempIDNums.Count - 1
For SelectedItemCounter As Integer = 0 To TextBoxDoubles.Count - 1
If TempIDNums(ListItemCounter) = TextBoxDoubles(SelectedItemCounter) Then
ListBox1.SetSelected(ListItemCounter, True)
End If
Next
Next
End If
I am writing a code that highlight the duplicate words in a text. The code is working well when I add a button and the user have to press on the button to check for duplicates.
But I want to make an auto-checking code. I set my code in a subroutine that Handles RichTextBox.TextChanged. The problem is the code selects the target word and highlight it but the selection remains so when a new letter is typed, it clear what has been highlighted.
Here is my code:
Private Sub RichTextBox_TextChanged(sender As Object, e As EventArgs) Handles RichTextBox.TextChanged
Try
Call duplicate_check()
Catch ex As Exception
MessageBox.Show("error in RichTextBox.TextChanged")
End Try
End Sub
duplicate check function:
Private Sub duplicate_check()
Try
' read line by line and get input
Dim LineByLineInput() As String = RichTextBox.Lines
Dim selectionStart, selectionLength As Integer
Dim i, j As Integer
For lineNumber = 0 To UBound(LineByLineInput)
selectionStart = 0
selectionLength = 0
'get index of first char index in the current line
Dim count As Integer = lineNumber
While count <> 0
selectionStart += RichTextBox.Lines(count - 1).Length + 1
count -= 1
End While
' get line as string
Dim line As String = RichTextBox.Lines(lineNumber)
' split line into array of strings
Dim input() As String = line.Split(" ")
'check for duplicates
i = 0
For j = i + 1 To UBound(input)
If input(i) = input(j) Then 'compare each 2 consecutive words if they are the same
selectionStart += input(i).Length + 1
selectionLength = input(i).Length
RichTextBox.SelectionStart = selectionStart
RichTextBox.SelectionLength = selectionLength
RichTextBox.SelectionBackColor = Color.Yellow
Else
selectionStart += input(i).Length + 1
End If
i += 1
Next
Next
Catch ex As Exception
MessageBox.Show("error duplicate_check()")
End Try
End Sub
After your duplicate_check call, have you tried to set the selection of the RichTextBox back to the old position ?
See below :
Private Sub RichTextBox1_TextChanged(sender As Object, e As System.EventArgs) Handles RichTextBox1.TextChanged
Try
' Get current position
Dim cur_pos As Integer = Me.RichTextBox.SelectionStart
Call duplicate_check()
' Set back to old position
Me.RichTextBox.SelectionStart = cur_pos
' Unselect what your sub duplicate_check has selected
Me.RichTextBox1.SelectionLength = 0
Catch ex As Exception
MessageBox.Show("error in RichTextBox.TextChanged")
End Try
End Sub
If this solution is good for you, you should change your duplicate_check Sub to make this change and not in the RichTextBox1_TextChanged Sub
I am getting a cast exception and I have re-written this code a large number of times. I am getting the exception on the following line:
If (CInt(hHurricaneYear) < CInt(_strYears(hAverage))) Then
And I am only getting results in the lblNumberOfHurricans. the other two labels are not showing any results. I thought I was getting it when the cast exception showed up.
Can anyone suggest how to get the results and stop the exception?
Here is what I have so far (well at least the last try).
Option Strict On
Public Class frmHurricaneStatistics
' Class level Private variables.
Public Shared _intSizeOfArray As Integer = 20
Private _strYears(_intSizeOfArray) As String
Private _intNumberOfHurricans(_intSizeOfArray) As Integer
Private Sub frmHurricaneStatistics_Load(sender As Object, e As EventArgs
) Handles MyBase.Load
' This load event reads the inventory text file and fills
' the ComboBox object with the Hurricane Statistics.
' Initialize an instace of the streamreader object and declare variables.
Dim objReader As IO.StreamReader
Dim strHurricaneStatistics As String = "Hurricanes.txt"
Dim intCount As Integer = 0
Dim intFill As Integer
Dim strFileError As String = "The file is not available. Please restart the
application when the file is available."
' Verify the Hurricane.txt file exists.
If IO.File.Exists(strHurricaneStatistics) Then
objReader = IO.File.OpenText(strHurricaneStatistics)
' Read the file line by line until the file is completed.
Do While objReader.Peek <> -1
_strYears(intCount) = objReader.ReadLine()
_intNumberOfHurricans(intCount) = Convert.ToInt32(objReader.ReadLine())
intCount += 1
Loop
objReader.Close()
' The ComboBox objext is filled with the Years for Hurricanes.
For intFill = 0 To (_strYears.Length - 1)
cmbYears.Items.Add(_strYears(intFill))
Next
Else
MsgBox(strFileError, , "Error")
Close()
' If ComboBox is filled then enable the Display Statistics button.
'btnDisplayStatistics.Enabled = True
End If
End Sub
Private Sub btnDisplayStatistics_Click(sender As Object, e As EventArgs
) Handles btnDisplayStatistics.Click
' This click event calls the sub procedures for the selected years and
' the number of hurricans in that year.
Dim intSelectedYear As Integer
Dim strMissingSelection As String = "Missing Selection"
Dim strSelectAYearError As String = "Please Select a Year"
' If the ComboBox object has a selection, Display Statistics.
If cmbYears.SelectedIndex >= 0 Then
intSelectedYear = cmbYears.SelectedIndex
Else
MsgBox(strSelectAYearError, , strMissingSelection)
End If
Private Sub btnDisplayStatistics_Click(sender As Object, e As EventArgs
) Handles btnDisplayStatistics.Click
' This click event calls the sub procedures for the selected years and
' the number of hurricans in that year.
Dim intSelectedYear As Integer
Dim strMissingSelection As String = "Missing Selection"
Dim strSelectAYearError As String = "Please Select a Year"
' If the ComboBox object has a selection, call the Display Statistics procedure.
If cmbYears.SelectedIndex >= 0 Then
intSelectedYear = cmbYears.SelectedIndex
Else
MsgBox(strSelectAYearError, , strMissingSelection)
End If
' This procedure MakeLabelsVisible Is called to display the labels
' And the results.
MakeLabelsVisible()
Dim hHurricaneAverage As Integer
Dim hHurricaneYear As Integer = 0
For hAverage As Integer = 0 To _strYears.Length - 1
If (CInt(hHurricaneYear) < CInt(_strYears(hAverage))) Then
hHurricaneYear = CInt(CType(CInt(_strYears(hAverage)), String))
End If
hHurricaneAverage = hHurricaneAverage + CInt((_strYears.ToString))
hHurricaneAverage = CInt(hHurricaneAverage / _strYears.Length)
Next
' Display the statistics for the Storm Average in the selected Year
' and the most active year within the range of year.
lblNumberOfHurricanes.Text = "The Number of Hurricanes in the Year " &
_strYears(intSelectedYear) & " is " & _intNumberOfHurricans(intSelectedYear).ToString() & "."
lblAvergeNumberHurricanes.Text = "The Average Number of Storms was " &
hHurricaneAverage & " Hurricanes."
Dim intSizeOfArray As Integer = Nothing
lblMostStorms.Text = "The Year "(CInt(_strYears(CInt(hHurricaneYear.ToString())) & "
Had The Most Storms Between " & (_strYears(0) & _strYears(20).ToString)))
End Sub
Option strict on
Your error lies in that you are trying to convert an entire string array into an integer:
hHurricaneAverage = hHurricaneAverage + CInt((_strYears.ToString))
You will need to call the index of _strYears:
hHurricaneAverage = hHurricaneAverage + CInt((_strYears(hAverage).ToString))
This will also explain why the other labels do not update, because hHurricanAverage never gets calculated.