Read Random Lines From Text File

Hey does anyone know how when i calick a button on my form it will read a random line from a text file that i created and insert it in to a text box?

Thanks For Any Help.:p

Is your file small enough to fit it all into memory at the same time?

If so, load each line of your file into an array.

Generate a random number between 0 and the last element of the array.

That's your text!

If you don't want repeats, set the array element to null after you use it. (If you pick a null in future, guess again.)

If your file is too big to fit in memory, open it and get the length. Generate a random number less than the length of the file. Go there. Go forward until you hit a chr$(13) (or run off the end, in which case go to the start. Read from there util the next chr$(13) (or the end). That's your string.

Any bits of that you need the code for, or is the principle enough?

im afraid i didnt understand any of the above so if you could maybe show some examples that would be great

Thanks alot

Try this

VB Code:

Dim strFile() As String
Dim sFile As String
 
Open "MyFile" For Input As #1
    sFile = Input(LOF(1), 1)
    strFile = Split(sFile, vbCrLf)
Close #1
 
For I = 1 To 10
    Randomize Timer
    nLine = Int(Rnd * UBound(sFile))
    text1 = text1 & strFile(nLine) & vbCrLf
Next I

OK Thanks alot i tried that but it say "expected array" on the word "UBound" could you tell me what this means and what i have to do to fix the problem please.

Try changing UBound(sFile) to UBound(strFile)

Hope it workz!

Thanx,
Mikelo2k
:):):)

Thanks alot for the help that all works except it reads a few lines instead of just one. Does anyone know how to let it know the different lines?

Although a lot of people don't like the filesystemobject I'd suggest you have a look into the fso's textstream-object. You will have much less to worry about and easier control. Need to have a reference to the microsoft scripting runtime which will use a few kb of diskspace and memory, but oh well neither is a very rare ressource.

Helger

Try this. It should be a lot more memory efficient that Megatron's example (esp with large files) as it only ever stores 1 line instead of the whole file

VB Code:

Dim intFF As Long
Dim strLine As String
Dim intLine As Long
Dim intLines As Long
Dim intCurrent As Long
 
intFF = FreeFile
intLines = 0
 
' get number of lines in file
Open "c:\winnt\win.ini" For Input As #intFF
Do While Not EOF(intFF)
    Line Input #intFF, strLine
    intLines = intLines + 1
Loop
 
'now we know number of lines, we can generate a random number
Randomize
intLine = Int((intLines - 1 + 1) * Rnd + 1)
 
'we now want line# intline
Seek #intFF, 1
intCurrent = 1
 
Do While intCurrent <= intLine
    Line Input #intFF, strLine
    intCurrent = intCurrent + 1
Loop
Close #intFF
 
MsgBox "Line # " & intLine & " contains: " & Chr(34) & strLine & Chr(34)

thanks for the code. it works.