I am trying to compare two strings that I know are equal to each other, but it is always skipping to the else. I've tried everything, .Equals, =, IsNot, they all don't work! The frustrating part is that I know the strings are equal! Please take a look at my code and see if it there is possible anything wrong with it.
Public Class Form1
Dim log As String
WithEvents xworker As New System.ComponentModel.BackgroundWorker
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
xworker.RunWorkerAsync()
End Sub
Private Sub xWorker_DoWork(ByVal sender As Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles xworker.DoWork
Dim qWorker = CType(sender, System.ComponentModel.BackgroundWorker)
Dim client As New Net.WebClient
log = client.DownloadString("http://########/log.txt")
End Sub
Private Sub xWorker_Completed(ByVal sender As Object, ByVal e As System.ComponentModel.RunWorkerCompletedEventArgs) Handles xworker.RunWorkerCompleted
If log.Equals(RichTextBox1.Text) Then
xworker.RunWorkerAsync()
Else
RichTextBox1.Text = log
xworker.RunWorkerAsync()
End If
End Sub
End Class
You needed to listen to #SLaks and #Hans Passant, they were right on the money.
I setup your code sample and it worked correctly if the source log.txt file didn't have a line terminator in it. Once I added the line terminator I got the results your are getting.
From the command window:
>? RichTextBox1.Text.Length
14
>? log.length
15
Using the QuickWatch window, and TABing until the Value field was selected:
Log result:
"log test 1234" & vbCrLf & ""
RichTextBox result:
"log test 1234" & vbLf & ""
The fix to the problem depends on what will actually get written to the log.txt file. I assume that "log test 1234" is just development code. If you are only interested in a single line as a result code then make sure you are not writing a line terminator. If your result codes are more complicated then you will need to do more parsing on the result than just an Equals compare.
Try this instead.
If log.ToLower().Trim() = RichTextBox1.Text.ToLower().Trim() Then
I think this is case sensitve compare. You should convert both of the strings to upper or to lower and then compare them
If Log.ToLower() = RichTextBox1.Text.ToLower() Then
Or you can use String.Compare method and set third param to true to ignore case
If String.Compare(log, RichTextBox1.Text, True) = 0 Then
I've read that the RichTextBox can change line endings when Text gets set. So the Text property might be returning a string that is different than what was set. I haven't been able to verify, but you can probably devise a quick test of this theory.
Related
I am using indexOf but I cannot figure out where I made a mistake as the output gives a -1.
I realise I can copy the whole statement paragraph into the last line of the output but I was hoping it could pull it straight from the label.
Public Class Form1
Private Sub btnCompute_Click(sender As Object, e As EventArgs) Handles btnCompute.Click
Dim statement As String
Dim letter As String
statement = CStr(lblStatement.Text)
letter = CStr(txtLetter.Text)
txtOutput.Text = CStr(lblStatement.Text).IndexOf("letter")
'txtOutput.Text = letter.ToUpper & " first occurs in position " & statement.IndexOf(statement) & "."
End Sub
End Class
Here is a picture of the form:
Update: Thanks to #ADyson and #Slugsie for taking the time to respond to my call for help. As #Slugsie noted it was indeed down to the lower case in my screenshot. I am now researching how to make it work without being case-sensitive.
Final code
Public Class Form1
Private Sub btnCompute_Click(sender As Object, e As EventArgs) Handles btnCompute.Click
txtOutput.Text = lblStatement.Text.IndexOf((txtLetter.Text).ToUpper)
End Sub
End Class
.IndexOf("letter")
is looking for the literal text letter within the data the user enters in the text. in VB.NET (and most other programming languages), anything enclosed within quote marks is treated as a fixed string of text, to be interpreted as-is rather than processed or treated as program code.
To make it look for the contents of the letter variable instead (which looks like what you were intending) simply remove the quote marks:
.IndexOf(letter)
As an aside, your whole code could be much reduced - primarily the use of CStr is unnecessary, because the Text properties of the textbox and label already return a string - meaning you don't need to use CStr convert it - and also because you're not making use of all the variables you declared either.
You could re-write your whole sample much more succinctly as:
Public Class Form1
Private Sub btnCompute_Click(sender As Object, e As EventArgs) Handles btnCompute.Click
txtOutput.Text = lblStatement.Text.IndexOf(txtLetter.Text)
End Sub
End Class
I am working on a little morse code translation project and I cannot figure out how to detect when a certain key is in a textbox and replace it with the corresponding morse code dots and dashes in the correct spot.
For example if you type in "a b c" then i would like the program to check and put
".- -... -.-."
but it also needs to be dynamic so if you change up the order of your letters it can update the translation.
as of right now i have a key checking system where you can only type in one forward line and if you mess up you have to clear the whole box. thank you!
Here is a basic example of what I was suggesting in my comments above, i.e. using two separate TextBoxes and translating the whole text every time:
Private morseCodeDictionary As New Dictionary(Of Char, String) From {{"a"c, ".-"},
{"b"c, "-..."},
{"c"c, "-.-."}}
Private Sub inputTextBox_TextChanged(sender As Object, e As EventArgs) Handles inputTextBox.TextChanged
outputTextBox.Text = String.Join(" ",
inputTextBox.Text.
ToLower().
Select(Function(ch) morseCodeDictionary(ch)))
End Sub
Here's an implementation that doesn't use LINQ, so may be more understandable:
Private Sub inputTextBox_TextChanged(sender As Object, e As EventArgs) Handles inputTextBox.TextChanged
Dim characterStrings As New List(Of String)
For Each ch As Char In inputTextBox.Text
characterStrings.Add(morseCodeDictionary(ch))
Next
outputTextBox.Text = String.Join(" ", characterStrings)
End Sub
While copying from resources to a folder under appdata folder: i get an error, but I'm not finding any mistake in code..
Private Sub Help_Load(sender As Object, e As EventArgs) Handles MyBase.Load
File.WriteAllBytes(MainPath & "\Help.rtf", My.Resources.HelpRTF)
Dim HelpRTF = (MainPath & "\Help.rtf")
Helpbox.LoadFile(HelpRTF)
End Sub
HelpRTF is a .rtf file, MainPath is a directory under %appdata% folder
Error: Value of type 'String' cannot be converted to 'Byte()'.
Error at: My.Resources.HelpRTF
The reason why you get that error is because the second parameter of the File.WriteAllBytes() method takes a Byte(), not a String. If you want to write text (String) to a file, you can use the File.WriteAllText() method.
Since RTF's can contain images, text, etc. treating it as text can corrupt it and needless to say, encoding issues might occur. So, instead of using the File.WriteAllText() method, change the FileType of the HelpRTF resource to Binary instead of Text like this:
After that, you can use your code as it was:
Private Sub Help_Load(sender As Object, e As EventArgs) Handles MyBase.Load
File.WriteAllBytes(MainPath & "\Help.rtf", My.Resources.HelpRTF)
Dim HelpRTF = (SWinPath & "\Help.rtf")
Helpbox.LoadFile(HelpRTF)
End Sub
References:
File.WriteAllText - MSDN
File.WriteAllBytes - MSDN
I am attempting to read a .txt file that I successfully wrote with a separate program, but I keep getting the program stalling (aka no input/output at all, like it had an infinite loop or something). I get the message "A", but no others.
I've seen a lot of threads on sites like this one that list all sorts of creative ways to read from a file, but every guide I have found wants me to change the code between Msgbox A and Msgbox D. None of them change the result, so I'm beginning to think that the issue is actually with how I'm pointing out the file's location. There was one code (had something to do with Dim objReader As New System.IO.TextReader(FileLoc)), but when I asked for a read of the file I got the file's address instead. That's why I suspect I'm pointing to the .txt wrong. There is one issue...
I have absolutely no idea how to do this, if what I've done is wrong.
I've attached at the end the snippet of code (with every single line of extraneous data ripped out of it).
If it matters, the location of the actual program is in the "G01-Cartography" folder.
Private Sub GameMain_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
LoadMap("Map_Cygnus.txt")
End Sub
Private Sub LoadMap(FileLoc As String)
FileLoc = "C:\Users\Adam\Documents\Visual Studio 2013\Projects\G01-Cartography\Maps\" + FileLoc
MsgBox("A")
Using File As New StreamReader(FileLoc)
MsgBox("B")
Dim WholeMap = File.ReadLine()
MsgBox("C")
End Using
MsgBox("D")
End Sub
What does running this show you in the debugger? Can you open the Map_Cygnus.txt file in Notepad? Set a breakpoint on the first line and run the program to see what is going on.
Private BaseDirectory As String = "C:\Users\Adam\Documents\Visual Studio 2013\Projects\G01-Cartography\Maps\"
Private Sub GameMain_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
Dim WholeMap = File.ReadAllText(Path.Combine(BaseDirectory, "Map_Cygnus.txt"))
Debug.Print("Size Of Map: {0}", WholeMap.Length)
End Sub
It looks like you're using the correct methods/objects according to MSDN.
Your code runs for me in an new VB console app(.net 4.5)
A different approach then MSGBOXs would be to use Debug.WriteLine or Console.WriteLine.
If MSGBOX A shows but not B, then the problem is in constructing the stream reader.
Probably you are watching the application for output but the debugger(visual studio) has stopped the application on that line, with an exception. eg File not found, No Permission, using a http uri...
If MSGBOX C doesn't show then problem is probably that the file has problems being read.
Permissions?
Does it have a Line of Text?
Is the folder 'online'
If MSGBOX D shows, but nothing happens then you are doing nothing with WholeMap
See what is displayed if you rewite MsgBox("C") to Debug.WriteLine("Read " + WholeMap)
I have a few suggestions. Firstly, use Option Strict On, it will help you to avoid headaches down the road.
The code to open the file is correct. In addition to avoiding using MsgBox() to debug and instead setting breakpoints or using Debug.WriteLine(), wrap the subroutine in a Try...Catch exception.
Private Sub GameMain_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
LoadMap("Map_Cygnus.txt")
End Sub
Private Sub LoadMap(FileLoc As String)
Try
FileLoc = "C:\Users\Adam\Documents\Visual Studio 2013\Projects\G01-Cartography\Maps\" + FileLoc
MsgBox("A")
Using File As New StreamReader(FileLoc)
MsgBox("B")
Dim WholeMap = File.ReadLine() 'dimming a variable inside a block like this means the variable only has scope while inside the block
MsgBox("C")
End Using
MsgBox("D")
Catch ex As Exception
MsgBox(ex.ToString)
End Try
End Sub
Note that you normally should only catch whatever exceptions you expect, but I generally catch everything while debugging things like this.
I would also like to point out that you are only reading one line out of the file into the variable WholeMap. That variable loses scope as soon as the End Using line is hit, thereby losing the line you just read from the file. I'm assuming that you have the code in this way because it seems to be giving you trouble reading from it, but thought I would point it out anyway.
Public Class GameMain
Private WholeMap As String = ""
Private Sub GameMain_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
LoadMap("Map_Cygnus.txt")
End Sub
Private Sub LoadMap(FileLoc As String)
Try
FileLoc = "C:\Users\Adam\Documents\Visual Studio 2013\Projects\G01-Cartography\Maps\" + FileLoc
Using File As New StreamReader(FileLoc)
WholeMap = File.ReadLine() 'dimming the variable above will give all of your subs inside class Form1 access to the contents of it (note that I've removed the Dim command here)
End Using
Catch ex As Exception
MsgBox(ex.ToString)
End Try
End Sub
End Class
I'm trying to make a textbox where the user inputs a string like "Joe was here" and that same string is "written" on the text file at the same time. Most of the questions asked around is using a button that helps save the string to the text file.
It works great, however for some unknown reason the text file can't register the last key pressed. In other words if I wrote "Joe was here" in my textbox, the text file has "Joe was her" where the "e" is missing.It's always the last key :(
This is a general view of the code I have that makes it work
Private Sub TextBox1_KeyPress(sender As Object, e As KeyPressEventArgs) Handles TextBox1.KeyPress
Dim File_name As String = "path where text file is saved at"
If System.IO.File.Exists(File_name) Then
Dim objWriter As New System.IO.StreamWriter(File_name)
objWriter.Write(TextBox1.Text)
objWriter.Close()
End If
End Sub
Maybe I'm missing something? Perhaps I'm using the wrong type of event as I'm using keypress instead of keydown or something else?
i just did a quick sample with your code and gives the exact issue, so i changed to the event keyup and it worked.
reason could be the time that keypress event processes or receives the key code at least in keyup first receive all the text and then executes the call to the process.
Private Sub TextBox1_TextChanged(sender As Object, e As EventArgs) Handles TextBox1.TextChanged
My.Computer.FileSystem.WriteAllText("C:\test.txt", TextBox1.Text, False)
End Sub