Saving contents of multiple text boxes and possibly combo boxes - vb.net

I'm working on a basic application that lets you track experience earned across up to 3 skills. The names of the skills are in a combo box (not sure if the best) and the beginning and ending values are in text boxes.
I want to add a save button that saves the ending values and selected skills, when pressing the load button it would populate the combo boxes with saved skills and input the old ending values into the new beginning ones.
I've been working on this all day, searching for a long time I've come up with similar solutions but nothing seems to work right. I'm still a bit of a beginner so some of the solutions I don't understand. Also, this has to work for VBNet.
The closest solution I've come across is:
File.WriteAllText("C:\Data.txt", String.Join("|", new String({TextBox1.Text, TextBox2.Text, TextBox3.Text}))
I'd like the file to stay with the project in the main directory though. Would this work for combo boxes as well, and how to load the values back in?
I'm still a newbie to VB, hope this question makes sense.

If I get your idea right, please find some functions below if they can help:
One can read (or write) text:
This one can populate the needed string to 3 textboxes txtSkill1, txtSkill2, txtSkill3
Sub ReadTextFile()
Dim lineCount As Integer = 0
Dim rndInstance As New Random
Dim idx As Integer = 0
Dim selectedLine As String = ""
Dim txt As String = "Skills.txt"
If Not File.Exists(txt) Then
File.Create(txt).Dispose()
Dim objWriter As New System.IO.StreamWriter(txt, True)
' 2 sample text lines:
objWriter.WriteLine("Negotiating - Interpersonal - Working independently")
objWriter.WriteLine("Goal oriented - Leadership - Teamwork")
objWriter.Close()
End If
lineCount = File.ReadAllLines(txt).Length
idx = rndInstance.Next(1, lineCount + 1) ' the index can be random if you want, or run from (1 to lineCount)
selectedLine = ReadLineWithNumberFrom(txt, idx)
Dim pattern As String = "-" ' split on hyphens
Dim subStrings() As String = Regex.Split(selectedLine, pattern)
txtSkill1.Text = subStrings(0)
txtSkill2.Text = subStrings(1)
txtSkill3.Text = subStrings(2)
End Sub
One can read a string from a specific line number:
Function ReadLineWithNumberFrom(filePath As String, ByVal lineNumber As Integer) As String
Using file As New StreamReader(filePath)
' Skip all preceding lines:
For i As Integer = 1 To lineNumber - 1
If file.ReadLine() Is Nothing Then
Throw New ArgumentOutOfRangeException("lineNumber")
End If
Next
' Attempt to read the line you're interested in:
Dim line As String = file.ReadLine()
If line Is Nothing Then
Throw New ArgumentOutOfRangeException("lineNumber")
End If
' Succeeded!
Return line
End Using
End Function
Now with the functions allow you to write to any text file, to read from any text file, from any line number, with specific separator (here is the hyphen -- char), you can Save and Load any string you need.

Related

Is it possible to use String.Split() when NewLine is the delimiter?

I have a question which asks me to calculate something from an input file. The problem is, the lines in the file don't use any special character as delimiter, like , or |. I will show it down below.
Data Communication
20
Visual Basic
40
The output I need to write to another file should look like this:
Data communication 20
Visual Basic 40
Total Books : 60
The problem is, how can I specify the delimiter? Like when there is a symbol as in strArray = strLine.Split(","). Since there is nothing I can use as delimiter, how can I split the file content?
There's no real need to split the text in the input file, when you can read a file line by line using standard methods.
You can use, e.g., a StreamReader to read the lines from the source file, check whether the current line is just text or it can be converted to a number, using Integer.TryParse and excluding empty lines.
Here, when the line read is not numeric, it's added as a Key in a Dictionary(Of String, Integer), unless it already exists (to handle duplicate categories in the source file).
If the line represents a number, it's added to the Value corresponding to the category Key previously read, stored in a variable named previousLine.
This setup can handle initial empty lines, empty lines in the text body and duplicate categories, e.g.,
Data Communication
20
Visual Basic
40
C#
100
Visual Basic
10
Other stuff
2
C++
10000
Other stuff
1
If a number is instead found in the first line, it's treated as a category.
Add any other check to handle a different structure of the input file.
Imports System.IO
Imports System.Linq
Dim basePath = "[Path where the input file is stored]"
Dim booksDict = New Dictionary(Of String, Integer)
Dim currentValue As Integer = 0
Dim previousLine As String = String.Empty
Using sr As New StreamReader(Path.Combine(basePath, "Books.txt"))
While sr.Peek > -1
Dim line = sr.ReadLine().Trim()
If Not String.IsNullOrEmpty(line) Then
If Integer.TryParse(line, currentValue) AndAlso (Not String.IsNullOrEmpty(previousLine)) Then
booksDict(previousLine) += currentValue
Else
If Not booksDict.ContainsKey(line) Then
booksDict.Add(line, 0)
End If
End If
End If
previousLine = line
End While
End Using
Now, you have a Dictionary where the Keys represent categories and the related Value is the sum of all books in that category.
You can Select() each KeyValuePair of the Dictionary and transform it into a string that represents the Key and its Value (Category:Number).
Here, also OrderBy() is used, to order the categories alphabetically, in ascending order; it may be useful.
File.WriteAllLines is then called to store the strings generated.
In the end, a new string is appended to the file, using File.AppendAllText, to write the sum of all books in all categories. The Sum() method sums all the Values in the Dictionary.
Dim newFilePath = Path.Combine(basePath, "BooksNew.txt")
File.WriteAllLines(newFilePath, booksDict.
Select(Function(kvp) $"{kvp.Key}:{kvp.Value}").OrderBy(Function(s) s))
File.AppendAllText(newFilePath, vbCrLf & "Total Books: " & booksDict.Sum(Function(kvp) kvp.Value).ToString())
The output is:
C#:100
C++:10000
Data Communication:20
Other stuff:3
Visual Basic:50
Total Books: 10173
Sure.. System.IO.File.ReadAllLines() will read the whole file and split into an array based on newlines, so you'll get an array of 4 elements. You can process it with a flipflop boolean to get alternate lines, or you can try and parse the line to a number and if it works, then its a number and if not, it's a string. If it's a number take the string you remembered (using a variable) from the previous loop
Dim arr = File.ReadALlLines(...)
Dim isStr = True
Dim prevString = ""
For Each s as String in arr
If isStr Then
prevString = s
Else
Console.WriteLine($"The string is {prevString} and the number is {s}")
End If
'flip the boolean
isStr = Not isStr
Next s
I used File.ReadAllLines to get an array containing each line in the file. Since the size of the file could be larger than the sample shown, I am using a StringBuilder. This save having to throw away and create a new string on each iteration of the loop.
I am using interpolated strings indicated by the $ preceding the quotes. This allows you to insert variables into the string surrounded by braces.
Note the Step 2 in the For loop. i will increment by 2 instead of the default 1.
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim lines = File.ReadAllLines("input.txt")
Dim sb As New StringBuilder
Dim total As Integer
For i = 0 To lines.Length - 2 Step 2
sb.AppendLine($"{lines(i)} {lines(i + 1)}")
total += CInt(lines(i + 1))
Next
sb.AppendLine($"Total Books: {total}")
TextBox1.Text = sb.ToString
End Sub

Read complex text file using Vb.net

File Structure
RECORD
1234567890,123456789,1234567,Address1,,City,State,Zip,USA,Phone,,,,,,,,,
EmpName,DBAName,ID,,Address1,,Address1,City,60603,USA,234567890,,,,
C,03/13/2017,,1,2,
RECORD
1234567890,123456789,1234567,Address1,,City,State,Zip,USA,Phone,,,,,,,,,
EmpName2,DBAName2,ID2,,Address2,,Address2,City2,60603,USA,234567890,,,,
C,03/13/2017,,1,2,
Looking at the above file structure, I want to loop through file and for each record(RECORD), I want to put next three lines in one array and then next record in separate array.
I am looking for skeleton code, I am very new in programming using stream readers.
Code so far
Dim read As New System.IO.StreamReader("C:\New Text.txt")
Dim a As String
For Each a In read.ReadLine
If read.ReadLine.Equals("RECORD") Then
\\How do I read next 3 lines and put them in one array with comma delimiter
End If
Next
You need a data structure where you will keep the lines loaded and then start your loop
' Here you will keep the 3 lines block joined together and splitted on comma
Dim records = new List(Of String())()
Using read As New System.IO.StreamReader("C:\New Text.txt")
Dim a As String
' Read each line (Assuming that we start with a RECORD line
For Each a In read.ReadLine
' Do not read another line, but just test what is present in the string
If a.Equals("RECORD") Then
' Now read the 3 following lines....
Dim line1 = read.ReadLine
Dim line2 = read.ReadLine
Dim line3 = read.ReadLine
'Join the lines togeter
Dim record = string.Join("", line1, line2, line3).
' Split on the comma to produce an array of strings. The fields.
Dim fields = record.Split(","c)
records.Add(fields)
End If
Next
End Using
Of course this should be enhanced using a proper class that describe your inputs where each property of the class represent a field of the CSV file loaded. And then you could change the List(Of String()) to a List(Of YourClassData)
Keep in mind that this solution is extremely dependant of an exact file structure. A line with the "RECORD" content should be always followed by three lines of data. (No blank lines allowed between the three data lines)
Dim read As New System.IO.StreamReader("C:\New Text.txt")
//I usually only do C#, but rough VB.NEt code: I did not rcreate your array for you, figured you got that :-)
Dim a As String
Dim myConcatString as String
For Each a In read.ReadLine
Dim myReadLine as String
myReadLine = read.ReadLine
If myReadLine.Equals("RECORD") Then
myConcatString = myConcatString & myReadLine
\\How do I read next 3 lines and put them in one array with comma delimiter
else
//add myConcatString to array if not null....
myConcatString =""
End If
Next

VB Import variable then use part 1 in dropdown and display part 2 to match selection in part 1

I'm using Visual studio to build a small utility.
I'm importing variables from a text file (this makes my program expandable in the future).
I'm running into a road block trying to split the variables into usable parts.
The text file is set up as such:
Game1:flshflhdlsfsdsfs
Game2:ugdjgndrgbdvdnjd
Game3:gnnereknengievke
And the code I've gathered from searching around trying to understand how I could do this is (It's gone through multiple rewrites but I feel this is probably the closest I've gotten):
Dim value As String = File.ReadAllText("Games.txt")
Dim cut_at As String = ":"
Dim x As Integer = InStr(value, cut_at)
Dim string_before As String = value.Substring(0, x - 2)
Dim string_after As String = value.Substring(x + cut_at.Length - 1)
Games_drp.Items.AddRange(string_before)
When I run a test like this, I get an error that String_before cannot be converted to an object. I tried switching "Dim string_before As String = value.Substring(0, x - 2)" to Dim string_before As Object = value.Substring(0, x - 2), but the dropdown that's supposed to be populated by at least one of the entries before the : has absolutely nothing in it.
Being pretty new at VB and feeling like I've exhausted pretty much every way I could think of searching in google and trying to piece together various bits of information, I figure I'd try asking my own direct question:
How would I go about reading all the lines from a text file, then splitting before the : to fill a combobox, and using a label to display the string after the : matching which ever entry is selected in the dropdown.
Thanks in advance for any help.
EDIT with full code:
Imports System.IO
Public Class Saves_frm
Private Sub Saves_frm_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim value As String = File.ReadAllText("Games.txt")
Dim cut_at As String = ":"
Dim x As Integer = InStr(value, cut_at)
Dim string_before As String = value.Substring(0, x - 2)
Dim string_after As String = value.Substring(x + cut_at.Length - 1)
Games_drp.Items.AddRange(string_before)
End Sub
End Class
When run as is, I get an error that 'string_before' can't be converted from a string to an object, but when I make the following change from:
Dim string_before As String = value.Substring(0, x - 2)
to:
Dim string_before As Object = value.Substring(0, x - 2)
The error goes away, but the dropdown remains blank.
It's easier to use File.ReadAllLines, as it returns an array with all the file's lines. Then, you can loop through the lines, splitting each line and adding the result to the ListBox. This should be an example, but feel free to correct any mistakes I made, as I wrote it on my phone and it's been a long time since I used VB.
Dim lines() As String = File.ReadAllLines("file.txt")
For Each line As String In lines
Dim split() As String = line.Split(":"c)
gDic.Add(split(0), split(1))
Next
EDIT: Then, you most certainly want a dictionary that contains the name and the data, check the updated code.
Then, add the names by looping through gDic.Keys. When a name is selected, access its value with gDic("key").

VBNET Reading a specific column on a line in a text file

I have saved written a text file and it currently reads:
"first","surname","pass"
I want to read the password column so the 3rd one and define that as a variable. Its basically for a login, if pass in text file matches the entered pass (from user).
I have searched for about an hour now and no luck. Could someone guide me to a correct path.
Thanks.
Simple example of reading a small file line by line and splitting each one into fields:
' get the values from the user somehow:
Dim first As String = "James"
Dim surname As String = "Bond"
Dim pass As String = "007"
Dim validated As Boolean = False ' assume wrong until proven otherwise
' check the file:
Dim fileName As String = "c:\some folder\path\somefile.txt"
Dim lines As New List(Of String)(System.IO.File.ReadAllLines(fileName))
For Each line As String In lines
Dim values() As String = line.Split(",")
If values.Length = 3 Then
If values(0).Trim(Chr(34)) = first AndAlso
values(1).Trim(Chr(34)) = surname AndAlso
values(2).Trim(Chr(34)) = pass Then
validated = True
Exit For
End If
End If
Next
' check the result
If validated Then
MessageBox.Show("Login Successful!")
Else
MessageBox.Show("Login Failed!")
End If
If this is a CSV file, as seems to be the case, then the easiest way to read it will be with the TextFieldParser class. The MSDN already provides an excellent example for how to use it to read a CSV file, so I won't bother reproducing it here.

Visual Basic Read File Line by Line storing each Line in str

I am trying to loop through the contents of a text file reading the text file line by line. During the looping process there is several times I need to use the files contents.
Dim xRead As System.IO.StreamReader
xRead = File.OpenText(TextBox3.Text)
Do Until xRead.EndOfStream
Dim linetext As String = xRead.ReadLine
Dim aryTextFile() As String = linetext.Split(" ")
Dim firstname As String = Val(aryTextFile(0))
TextBox1.Text = firstname.ToString
Dim lastname As String = Val(aryTextFile(0))
TextBox2.Text = lastname.ToString
Loop
Edit: What I am trying to do is read say the first five items in a text file perform some random processing then read the next 5 lines of the text file.
I would like to be able to use the lines pulled from the text file as separated string variables.
It is not clear why you would need to have 5 lines stored at any time, according to your code sample, since you are only processing one line at a time. If you think that doing 5 lines at once will be faster - this is unlikely, because .NET maintains caching internally, so both approaches will probably perform the same. However, reading one line at a time is a much more simple pattern to use, so better look into that first.
Still, here is an approximate version of the code that does processing every 5 lines:
Sub Main()
Dim bufferMaxSize As Integer = 5
Using xRead As New System.IO.StreamReader(TextBox3.Text)
Dim buffer As New List(Of String)
Do Until xRead.EndOfStream
If buffer.Count < bufferMaxSize Then
buffer.Add(xRead.ReadLine)
Continue Do
Else
PerformProcessing(buffer)
buffer.Clear()
End If
Loop
If buffer.Count > 0 Then
'if line count is not divisible by bufferMaxSize, 5 in this case
'there will be a remainder of 1-4 records,
'which also needs to be processed
PerformProcessing(buffer)
End If
End Using
End Sub
Here is mine . Rely easy . Just copy the location from the file and copy1 folder to does locations . This is my first program :) . ready proud of it
Imports System.IO
Module Module1
Sub Main()
For Each Line In File.ReadLines("C:\location.txt".ToArray)
My.Computer.FileSystem.CopyDirectory("C:\Copy1", Line, True)
Next
Console.WriteLine("Done")
Console.ReadLine()
End Sub
End Module