I need help, I don't know why the array for the quantity in my input file strArr(1) having an error that says that the input string was not in a correct format.
Dim objReader As IO.StreamReader
Dim objWriter As New IO.StreamWriter("C:\Users\user\Desktop\StationeryFolder\output.txt")
Dim strLine As String
Dim strName As String
Dim intQuantity As Integer
Dim intTotal As Integer
Dim strArr() As String
If IO.File.Exists("C:\Users\user\Desktop\StationeryFolder\input.txt") = True Then
objReader = IO.File.OpenText("C:\Users\user\Desktop\StationeryFolder\input.txt")
Else
MsgBox("File is not exist")
Close()
End If
Do While objReader.Peek <> -1
strLine = objReader.ReadLine()
strArr = strLine.Split(" ")
strName = strArr(0)
intQuantity = Convert.ToInt32(strArr(1)) //this is where the error occurs
intTotal = intTotal + intQuantity
lstDisplay.Items.Add(strName & " " & intQuantity.ToString())
objWriter.WriteLine(strName & " " & intQuantity.ToString())
Loop
lstDisplay.Items.Add("Total Quantity of Stationeries are: " & intTotal.ToString())
objWriter.WriteLine("Total Quantity of Stationeries are: " & intTotal.ToString())
objReader.Close()
objWriter.Close()
Inside the input file:
Markers
15
Pens
25
I used the .net File class instead of streams. ReadAllLine returns an array of the lines in the file. I used a StringBuilder which is mutable (changeable) unlike a String. Saves the code from creating and throwing away several strings. I have used interpolated strings indicated by the $ before the quotes. This allows inserting variables directly into the string surrounded by braces.
Private Sub OPCode()
Dim inputPath = "C:\Users\user\Desktop\StationeryFolder\input.txt"
If Not IO.File.Exists(inputPath) Then
MsgBox("File does not exist")
Close()
End If
Dim lines = File.ReadAllLines(inputPath)
Dim total As Integer
Dim sb As New StringBuilder
For i = 0 To lines.Length - 2 Step 2
lstDisplay.Items.Add($"{lines(i)} {lines(i + 1)}")
sb.AppendLine($"{lines(i)} {lines(i + 1)}")
total += CInt(lines(i + 1))
Next
lstDisplay.Items.Add($"Total Quantity of Stationeries are: {total}")
sb.AppendLine($"Total Quantity of Stationeries are: {total}")
File.WriteAllText("C:\Users\user\Desktop\StationeryFolder\output.txt", sb.ToString)
End Sub
So I'm still a bit of a newbie when it comes to programming, hence why I'm using visual basic. I'm getting this exception raised repeatedly, but the variables that vb is saying have unassigned values have been given values in my code. Can anyone point out where I'm going wrong with this?
EDIT: just a few more details: the file exists, I can read from it using just the ReadLine method, but I need to split the fields so I can compare the scores and get the highest 2 scores
Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
Dim srdFile As System.IO.StreamReader
Dim strLine As String
Dim strField(1) As String
Dim strName() As String
Dim strScore() As String
Dim i = 0
srdFile = New System.IO.StreamReader("HighScores.dat")
rtbOut.AppendText("HighScores:" & vbNewLine & vbNewLine)
Do Until srdFile.Peek() = -1
strLine = srdFile.ReadLine()
strField = strLine.Split(",")
strName(i) = strField(0)
strScore(i) = strField(1)
rtbOut.AppendText(strName(i) & ", " & strScore(i) & vbNewLine)
i = i + 1
Loop
End Sub
Following two arrays are never initialized: strName and strScore
I don't know the logic, but one way would be to use a List(Of String) instead which does not need to get the correct size in the first place and can be resized. I would also use the Using-statement to dispose the stream properly:
Using srdFile As New System.IO.StreamReader("HighScores.dat")
Dim strLine As String
Dim strField(1) As String
Dim strName As New List(Of String)
Dim strScore As New List(Of String)
Dim i = 0
rtbOut.AppendText("HighScores:" & vbNewLine & vbNewLine)
Do Until srdFile.Peek() = -1
strLine = srdFile.ReadLine()
strField = strLine.Split(","c)
strName.Add(strField(0))
strScore.Add(strField(1))
rtbOut.AppendText(strName(i) & ", " & strScore(i) & vbNewLine)
i += 1
Loop
End Using
Side-note: i recommend to set Option Strict to On by default.
By the way, here is a completely different approach doing the same but with LINQ:
Dim lines = From line In IO.File.ReadLines("HighScores.dat")
Where Not String.IsNullOrWhiteSpace(line)
Let fields = line.Split(","c)
Let name = fields.First()
Let score = fields.Last()
Select String.Format("{0}, {1}", name, score)
rtbOut.Text = String.Join(Environment.NewLine, lines)
I find this more readable.
Before you use an array, you need to assign a fixed array size in the computer memory locations. You can do this by initialising an array with the number of array elements. In your code, you have not allocated any memory to strName() and strScore() before using them, hence the code will throw an exception.
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim srdFile As System.IO.StreamReader
Dim strLine As String
Dim strField(1) As String
Dim strName(10) As String ''fixed size array (Using List(Of T) is a better option)
Dim strScore(10) As String ''fixed size array (Using List(Of T) is a better option)
Dim i = 0
srdFile = New System.IO.StreamReader("HighScores.dat")
rtbOut.AppendText("HighScores:" & vbNewLine & vbNewLine)
Do Until srdFile.Peek() = -1
strLine = srdFile.ReadLine()
strField = strLine.Split(",")
strName(i) = strField(0)
strScore(i) = strField(1)
rtbOut.AppendText(strName(i) & ", " & strScore(i) & vbNewLine)
i = i + 1
Loop
End Sub
You can also create a dynamic array. Please follow Resizing an array at runtime in VB.NET on Stackoverflow about dynamic array.
I need to find a section header, in this case "[Store Hours]", in a text file that I'm using to save the settings for the program. I need to skip the header and replace the next 7 lines with the text that is in the text boxes. The code below currently deletes the header "[Store Hours]" and does not replace any of the lines.
Dim objFileName As String = "Settings.txt"
Private Sub BtnAdd_Click(sender As System.Object, e As System.EventArgs) Handles btnSaveHours.Click
Dim OutPutLine As New List(Of String)()
Dim matchFound As Boolean
For Each line As String In System.IO.File.ReadAllLines(objFileName)
matchFound = line.Contains("[Store Hours]")
If matchFound Then
'does not skip the header line
line.Skip(line.Length)
'Need to loop through this 7 times (for each day of the week)
'without reading the header again
For intCount = 0 To 6
Dim aryLabelDay() As String = {"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"}
Dim varLabelNameIn As String = "txt" & aryLabelDay(intCount).ToString & "In"
Dim varDropNameIn As String = "drp" & aryLabelDay(intCount).ToString & "In"
Dim varLabelNameOut As String = "txt" & aryLabelDay(intCount).ToString & "Out"
Dim varDropNameOut As String = "drp" & aryLabelDay(intCount).ToString & "Out"
Dim varTextBoxInControl() As Control = Me.Controls.Find(varLabelNameIn, True)
Dim varDropBoxInControl() As Control = Me.Controls.Find(varDropNameIn, True)
Dim varTextBoxOutControl() As Control = Me.Controls.Find(varLabelNameOut, True)
Dim varDropBoxOutControl() As Control = Me.Controls.Find(varDropNameOut, True)
Dim dymTextNameIn As TextBox = DirectCast(varTextBoxInControl(0), TextBox)
Dim dymDropNameIn As ComboBox = DirectCast(varDropBoxInControl(0), ComboBox)
Dim dymTextNameOut As TextBox = DirectCast(varTextBoxOutControl(0), TextBox)
Dim dymDropNameOut As ComboBox = DirectCast(varDropBoxOutControl(0), ComboBox)
Dim ReplaceLine As String
ReplaceLine = dymTextNameIn.Text & "," & dymDropNameIn.Text & "," & dymTextNameOut.Text & "," & dymDropNameOut.Text
'this doesn't replace anything
line.Replace(line, ReplaceLine)
intCount += 1
Next intCount
Else
OutPutLine.Add(line)
End If
Next
End Sub
Instead of using ReadAllLines simply use a streamreader and read the file line by line, like this;
Dim line As String
Using reader As StreamReader = New StreamReader("file.txt")
' Read one line from file
line = reader.ReadLine
If(line.Contains("[Store Hours]") Then
'The current line is the store hours header, so we skip it (read the next line)
line = reader.ReadLine
'Process the line like you want, and keep processing through the lines by doing a readline each time you want to progress to the next line.
End If
End Using
More importantly though, you should not be saving the settings for your program in a text file. They should be stored in app.config or web.config. See this question for further guidance on that.
Part of your confusion might be coming from the fact that you can't just replace part of a text file without copying it and overwriting it. One way, to do this, is to copy the file to memory changing the appropriate lines and overwriting the existing file with the new information. Here's one way that can be done:
Private Sub BtnAdd_Click(sender As System.Object, e As System.EventArgs) Handles btnSaveHours.Click
Dim OutPutLine As New List(Of String)()
Dim sr As New StreamReader(objFileName)
While Not sr.EndOfStream
Dim line = sr.ReadLine
'Found the header so let's save that line to memory and add all the other _
info after it.
If line.Contains("[Store Hours]") Then
OutPutLine.Add(line)
'Need to loop through this 7 times (for each day of the week)
'without reading the header again
Dim aryLabelDay() As String = {"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"}
For intCount = 0 To 6
'even though we're not using the info from the file, calling _
Readline advances the file pointer so that the next iteration _
of the while loop we can finish reading the file.
If Not sr.EndOfStream Then
line = sr.ReadLine
Dim dymTextNameIn As TextBox = DirectCast(Me.Controls("txt" & aryLabelDay(intCount) & "In"), TextBox)
Dim dymDropNameIn As ComboBox = DirectCast(Me.Controls("drp" & aryLabelDay(intCount) & "In"), ComboBox)
Dim dymTextNameOut As TextBox = DirectCast(Me.Controls("txt" & aryLabelDay(intCount) & "Out"), TextBox)
Dim dymDropNameOut As ComboBox = DirectCast(Me.Controls("drp" & aryLabelDay(intCount) & "Out"), ComboBox)
OutPutLine.Add(dymTextNameIn.Text & "," & dymDropNameIn.Text & "," & dymTextNameOut.Text & "," & dymDropNameOut.Text)
End If
Next
Else
'Any line that isn't in that section gets copied as is.
OutPutLine.Add(line)
End If
End While
'Copy all the new info to the same file overwriting the old info.
File.WriteAllLines(objFileName, OutPutLine)
End Sub
On a side note. The Controls collection is indexed by number or name which makes it fairly simple to access the appropriate control just by knowing its name.
Thanks for the help I actually figured it out and this is the final code I used
Private Sub btnSaveHours_Click(sender As System.Object, e As System.EventArgs) Handles btnSaveHours.Click
Dim intOutPutLine As New List(Of String)()
Dim blnSearchString As Boolean
Dim intLineCount As Integer = -1
Dim intLoopCount As Integer
For Each line As String In System.IO.File.ReadAllLines(objFileName)
blnSearchString = line.Contains("[Store Hours]")
If blnSearchString Then
intLineCount = intOutPutLine.Count
line.Remove(0)
intLoopCount = 0
ElseIf intLineCount = intOutPutLine.Count And intLoopCount < 7 Then
line.Length.ToString()
line.Remove(0)
intLoopCount += 1
Else
intOutPutLine.Add(line)
End If
Next
System.IO.File.WriteAllLines(objFileName, intOutPutLine.ToArray())
Dim objFileWrite As New StreamWriter(objFileName, True)
If File.Exists(objFileName) Then
objFileWrite.WriteLine("[Store Hours]")
Dim varMe As Control = Me
Call subConvertFrom12to24Hours(objFileWrite, varMe)
Else
objFileWrite.WriteLine("[Store Hours]")
Dim varMe As Control = Me
Call subConvertFrom12to24Hours(objFileWrite, varMe)
End If
Call btnClear_Click(sender, e)
End Sub
I have such kind of data in a text file:
12343,M,Helen Beyer,92149999,21,F,10,F,F,T,T,T,F,F
54326,F,Donna Noble,92148888,19,M,99,T,F,T,F,T,F,T
99999,M,Ed Harrison,92147777,28,F,5,F,F,F,F,F,F,T
88886,F,Amy Pond,92146666,31,M,2,T,F,T,T,T,T,T
37378,F,Martha Jones,92144444,30,M,5,T,F,F,F,T,T,T
22444,M,Tom Scully,92145555,42,F,6,T,T,T,T,T,T,T
81184,F,Sarah Jane Smith,92143333,22,F,5,F,F,F,T,T,T,F
97539,M,Angus Harley,92142222,22,M,9,F,T,F,T,T,T,T
24686,F,Rose Tyler,92142222,22,M,5,F,F,F,T,T,T,F
11113,F,Jo Grant,92142222,22,M,5,F,F,F,T,T,T,F
I want to extract the Initial of the first name and complete surname. So the output should look like:
H. Beyer, M
D. Noble, F
E. Harrison, M
The problem is that I should not use String Split function. Instead I have to do it using any other way of string handling.
This is my code:
Public Sub btn_IniSurGen_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn_IniSurGen.Click
Dim vFileName As String = "C:\temp\members.txt"
Dim vText As String = String.Empty
If Not File.Exists(vFileName) Then
lbl_Output.Text = "The file " & vFileName & " does not exist"
Else
Dim rvSR As New IO.StreamReader(vFileName)
Do While rvSR.Peek <> -1
vText = rvSR.ReadLine() & vbNewLine
lbl_Output.Text += vText.Substring(8, 1)
Loop
rvSR.Close()
End If
End Sub
You can use the TextFieldParserClass. It will parse the file and return the results directly to you as a string array.
Using MyReader As New Microsoft.VisualBasic.FileIO.
TextFieldParser("c:\logs\bigfile")
MyReader.TextFieldType =
Microsoft.VisualBasic.FileIO.FieldType.Delimited
MyReader.Delimiters = New String() {","}
Dim currentRow As String()
'Loop through all of the fields in the file.
'If any lines are corrupt, report an error and continue parsing.
While Not MyReader.EndOfData
Try
currentRow = MyReader.ReadFields()
' Include code here to handle the row.
Catch ex As Microsoft.VisualBasic.FileIO.MalformedLineException
MsgBox("Line " & ex.Message &
" is invalid. Skipping")
End Try
End While
End Using
For your wanted result, you may changed
lbl_Output.Text += vText.Substring(8, 1)
to
'declare this first
Dim sInit as String
Dim sName as String
sInit = vText.Substring(6, 1)
sName = ""
For x as Integer = 8 to vText.Length - 1
if vText.Substring(x) = "," Then Exit For
sName &= vText.Substring(x)
Next
lbl_Output.Text += sName & ", " & sInit
But better you have more than one lbl_Output ...
Something like this should work:
Dim lines As New List(Of String)
For Each s As String In File.ReadAllLines("textfile3.txt")
Dim temp As String = ""
s = s.Substring(s.IndexOf(","c) + 1)
temp = ", " + s.First
s = s.Substring(s.IndexOf(","c) + 1)
temp = s.First + ". " + s.Substring(s.IndexOf(" "c), s.IndexOf(","c) - s.IndexOf(" "c)) + temp
lines.Add(temp)
Next
The list Lines will contain the strings you need.
Is there any tool that will convert a multiline text, to a compatible multiline string for Visual Studio 2008/2005?
For example:
line1
line2
line3
line4
Should become:
"line1" & _
"line2" & _
"line3" & _
"line4"
This kind of tool definitely falls in the do-it-yourself category. Start a new Windows Forms application. Paste the code shown below. Put a shortcut to the program on your desktop. To use it, drag a file from Explorer onto the form. Switch to Visual Studio and type Ctrl+V.
Public Class Form1
Public Sub New()
InitializeComponent()
Me.AllowDrop = True
End Sub
Protected Overrides Sub OnDragEnter(ByVal e As DragEventArgs)
If e.Data.GetDataPresent("FileDrop") Then e.Effect = DragDropEffects.Copy
End Sub
Protected Overrides Sub OnDragDrop(ByVal e As DragEventArgs)
Dim files = DirectCast(e.Data.GetData("FileDrop", False), String())
Dim txt As New System.Text.StringBuilder
Dim lines = System.IO.File.ReadAllLines(files(0))
For ix As Integer = 0 To lines.Length - 1
txt.Append("""" + lines(ix).Replace("""", """""") + """")
If ix < lines.Length - 1 Then txt.AppendLine(" & _")
Next
Clipboard.SetText(txt.ToString())
End Sub
End Class
The better mousetrap is to add the file as a resource instead of hard-coding the text.
Is this what you're looking for?
Dim testString As String = "line1" & vbCrLf & _
"line2" & vbCrLf & _
"line3" & vbCrLf & _
"line4"
Dim allLines() As String = Microsoft.VisualBasic.Strings.Split(testString, vbCrLf)
Dim strConverter As New System.Text.StringBuilder
For Each line As String In allLines
strConverter.Append("""" & line & """").Append(" & _").Append(vbCrLf)
Next
If allLines.Length > 0 Then strConverter.Length -= (" & _" & vbCrLf).Length
Dim convertedString As String = strConverter.ToString
A VS Macro for Pasting Long Text as String seems like perfect solution.