Read message from text file and display in message box in vb.net - vb.net

Question

JavaError.128 = "project creation failed. & vbLf & Please try again and if the problem persists then contact the administrator"
I am able to read this message from text file. the issue is vbLf is not considered as newline in msgbox. it prints vbLf in msgbox.
Using sr As System.IO.StreamReader = My.Computer.FileSystem.OpenTextFileReader(errorfilePath)
While ((sr.Peek() <> -1))
line = sr.ReadLine
If line.Trim().StartsWith("JavaError." & output) Then
isValueFound = True
Exit While
End If
End While
sr.Close()
End Using
If isValueFound Then
Dim strArray As String() = line.Split("="c)
MsgBox(strArray(1).Replace("""", "").Trim({" "c}))
End If

Answer 1

You can make all your code a simpler one line version using File.ReadAllLines and LINQ. This code will put all the lines starting with javaerror into the textbox, not just the first:
textBox.Lines = File.ReadAllLines(errorFilePath) _
.Where(Function(s) s.Trim().StartsWith("JavaError")) _
.Select(Function(t) t.Substring(t.IndexOf("= ") + 2).Replace(" & vbLf & ", Environment.NewLine)) _
.ToArray()
You need to Imports System.IO and System.Linq
This code reads all the lines of the file into an array, then uses LINQ to pull out only those starting with java error, then projects a new string of everything after the = with vbLf replaced with a newline, converts the enumerable projection to an array of strings and assigns it to the textBox lines
If you don't want all the lines but instead only the first:
textBox.Text = File.ReadLines(errorFilePath) _
.FirstOrDefault(Function(s) s.Trim().StartsWith("JavaError")) _
?.Substring(t.IndexOf("= ") + 2).Replace(" & vbLf & ", Environment.NewLine))
This one uses ReadLine instead of ReadALlLines - ReadLines works progressively, and it makes sense to be able to stop reading after we foundt he first rather than have the overhead of reading ALL (million) lines only to then end up pulling the first out and throwing 999,999 lines of effort away. So it's reading line by line, pulls out the first that starts with "JavaError" (or Nothing if there is no such line), then checks if Nothing came out (the ?) and skips the Substring if it was Nothing, or it does a Substring on everything after the = and replaces vbLf with newline
For a straight up mod of your original code:
Using sr As System.IO.StreamReader = My.Computer.FileSystem.OpenTextFileReader(errorfilePath)
While ((sr.Peek() <> -1))
line = sr.ReadLine
If line.Trim().StartsWith("JavaError." & output) Then
isValueFound = True
line = line.Replace(" & vbLf & ", Environment.NewLine))
'^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ added code
Exit While
End If
End While
sr.Close()
End Using
If isValueFound Then
Dim strArray As String() = line.Split("="c)
MsgBox(strArray(1).Replace("""", "").Trim({" "c}))
End If
Note that I've always made my replacement on & vbLf & with a space at each end to avoid stray spaces being left behind - if your file sometimes doesn't have them, consider using Regex to do the replace, e.g. Regex.Replace(line, " ?& vbLf & ?", Environment.NewLine

Answer 2

This could work:
Dim txtFile As String = "project creation failed. & vbLf & Please try again and if the problem persists then contact the administrator"
Dim arraytext() As String = txtFile.Split("&")
Dim txtMsgBox As String = Nothing
For Each row As String In arraytext
If Trim(row) = "vbLf" Then
txtMsgBox = txtMsgBox & vbLf
Else
txtMsgBox = txtMsgBox & Trim(row)
End If
Next
MsgBox(txtMsgBox)