Comparing two text files and extracting the unmatched strings

[velkalai]

Hi,
In vb.net, how to do a file comparison between two text files and extract out the unmatched string...

I've done the following comparison.. very basic one...

Private Function FileCompare(ByRef NewFile As Array, ByRef OldFile As Array) As String

Dim intI As Integer
Dim strNew, strOld, strTemp As String
Dim intposition As Integer
Dim strchar As String

For intI = LBound(OldFile) To UBound(OldFile)
strOld = OldFile(intI)
If (strOld <> "" And strOld <> " ") Then
intposition = 0
For Each strchar In NewFile
If (strchar <> "" And strchar <> " ") Then
intposition = InStr(strOld, strchar)
If (intposition = 0) Then
strTemp = strTemp & "," & strchar
Else
Exit For
End If
End If
Next
End If
Next
Return strTemp
End Function

But the drawback is,, the strTemp starts to have the first record onwards.. not the unmatched strings...

Any heads up will be much appreciated..

Thanks

[nmadd]

I don't see two text files, but since you are comparing two arrays, you can loop through them both and see what matches up. Maybe this will get you started:

Dim oldfile() As String = {"two", "four", "five", "six"}
Dim newfile() As String = {"one", "two", "three", "four"}
 
For i As Integer = 0 To oldfile.GetUpperBound(0) Step 1
    For j As Integer = 0 To newfile.GetUpperBound(0) Step 1
        If oldfile(i) = newfile(j) Then
            MessageBox.Show("New file contains " & oldfile(i).ToString())
        End If
    Next j
Next i