Text files too big for VB to handle

I am trying to write a program that loads a text file into
a richtextbox control by looping through the text one line
at a time. Each line is first compared with a default value,
say "". If the line matches then Don't print it to the screen.
When I run my code with small files it works just fine, but
when I run the code on a 2M text file, it takes hours. In fact
I've never seen it finish on pass on this file. There has to be
a more efficient method than the one I'm using.

Dim m_filename As String
Dim FileData As String
Dim TotalFile As String

Open m_filename For Input As #1

Do While Not EOF(1)
Line Input #1, FileData

If FileData = "" Then
' Do nothing
Else
TotalFile = TotalFile & FileData & vbCrLf
End If
Loop

RichTextBox1.Text = TotalFile

Add each inputted line to an array, then JOIN the array at the end and add the JOIN'ed value to the box.

u could try something like this, and see if it speeds up the process..

VB Code:

Open fileName For Binary As #1
            Text1.Text = Input(LOF(1), 1)
        Close #1

This is your problem:

TotalFile = TotalFile & FileData & vbCrLf


Try:

Code:

---

Dim m_filename As String
Dim FileData As String
Dim TotalFile() As String
Dim result() as string
Dim final as string
Open m_filename For Input As #1
FileData  = input(lof(1),1)
close #1
totalfile = split(filedata,vbcrlf) ' an array of lines
for x = 1 to ubound(totalfile)
    if totalfile(x) > "" then
        Redim Preserve result(ubound(result)+1)
        result(ubound(result)) = totalfile(x) & vbCrLf
    end if
next x
final = Join(result)
' final is now one giant string, like your old totalfile was

---

Maybe I missed something but why not just use:

VB Code:

rtb.LoadFile App.Path & "\myfile.txt", rtfText

You did say you are using a richtextbox right?

Thanks