VB.net read a text file and populate a combobox with specific extracted words

Question

I have a problem which is giving me a headache. I really thought someone would have asked this already, but days of reading and testing has been fruitless.

I have a text file which starts:

"Determining profile based on KDBG search...

     Suggested Profile(s) : WinXPSP2x86, WinXPSP3x86 (Instantiated with WinXPSP2x86)"

(The blank line between the two is not an error and neither are the spaces before 'Suggested')

I need to read the line starting 'Suggested...' only and extract every unique word starting 'Win' and populate a combobox with them. (i.e. 'WinXPSP2x86' and 'WinXPSP3x86')

I know i need to use the 'StreamReader' class and probably get a Regex going on, but, as a beginner, connecting it all together is beyond my knowledge at the moment.

Can anyone help? It would be much appreciated.

Answer 1

As some have already suggested:

• Use System.IO.File.ReadAllLines, if the file is not too big
• Iterate through the array of lines
• For each line, use the Split method to split on space
• Check the first three characters of each word

This works but does of course need some error checking etc:

        Dim lines() As String = System.IO.File.ReadAllLines("c:\temp\example.txt")

        Dim lineWords() As String
        For Each line As String In lines
            lineWords = line.Split(New Char() {" "}, System.StringSplitOptions.RemoveEmptyEntries)

            For Each word As String In lineWords
                If word.Length > 3 Then
                    If word.Substring(0, 3).ToUpper = "WIN" Then
                        cmbWords.Items.Add(word)
                    End If
                End If                
            Next
        Next

Answer 2

Imports System.IO
Public Class Form1

Private Sub Form1_Load( sender As Object,  e As EventArgs) Handles MyBase.Load

    ' BASIC is case sensitive and e is parameter so we will start
    ' new variables with the letter f.

    ' Read all lines of file into string array F.
    Dim F As String() = File.ReadAllLines("H:\Projects\35021241\Input.txt")
    ' F() is a 0 based array.  Assign 3 line of file to G.
    Dim G As String = F(2)
    ' On line 3 of file find starting position of the word 'win' and assign to H.
    ' TODO:  If it is not found H will be -1 and we should quit.
    Dim H As Integer = G.IndexOf("Win")
    ' Assign everything beginning at 'win' on line 3 to variable I.
    Dim I As String = G.Substring(H)
    ' The value placed in delimiter will separate remaining values in I.
    ' Place C after ending quote to represent a single character as opposed to a string.
    Dim Delimiter As Char = ","C
    ' J array will contain values left in line 3.
    Dim J As String() = I.Split(Delimiter)

    ' Loop through J array removing anything in parenthesis.
    For L = J.GetLowerBound(0) to J.GetUpperBound(0)
        ' Get location of open parenthesis.
        Dim ParenBegin As Integer = J(L).IndexOf("(")
        ' If no open parenthesis found continue.
        If ParenBegin <> -1 then
            ' Open parenthesis found.  Find closing parenthesis location
            ' starting relative to first parenthesis.
            Dim Temp As String = J(L).Substring(ParenBegin+1)
            ' Get location of ending parenthesis.
            Dim ParenEnd As Integer = Temp.IndexOf(")")
            ' TODO:  Likely an exception will be thrown if no ending parenthesis.
            J(L) = J(L).Substring(0,ParenBegin) & J(L).Substring(ParenBegin + ParenEnd +2)
            ' Change to include text up to open parenthesis and after closing parenthesis.
        End If
    Next L

    ' UnwantedChars contains a list of characters that will be removed.
    Dim UnwantedChars As String = ",()"""
    ' Check each value in J() for presence of each unwanted character.
    For K As Integer = 0 to (UnwantedChars.Length-1)
        For L = J.GetLowerBound(0) To J.GetUpperBound(0)
            ' Declare M here so scope will be valid at loop statement.
            Dim M As Integer = 0
            Do
                ' Assign M the location of the unwanted character or -1 if not found.
                M= J(L).IndexOf(UnwantedChars.Substring(K,1))
                ' Was this unwanted character found in this value?
                If M<>-1 Then
                    ' Yes - where was it found in the value?
                    Select Case M
                        Case 0  ' Beginning of value
                            J(L) = J(L).Substring(1)
                        Case J(L).Length    ' End of value.
                            J(L) = J(L).Substring(0,(M-1))
                        Case Else   ' Somewhere in-between.
                            J(L) = J(L).Substring(0,M) & J(L).Substring(M+1)
                    End Select
                Else
                    ' No the unwanted character was not found in this value.
                End If
            Loop Until M=-1 ' Go see if there are more of this unwanted character in the value.
        Next L  ' Next value.
    Next K  ' Next unwanted character.

    ' Loop through all the values and trip spaces from beginning and end of each.
    For L As Integer = J.GetLowerBound(0) To J.GetUpperBound(0)
        J(L) = J(L).Trim
    Next L  

    ' Assign the J array to the combobox.
    ComboBox1.DataSource = J

End Sub

End Class