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   Medium How can I check for the existance of files?

   Medium I'm trying to read a file with EOF's in it. I can't read past the first EOF.

   Medium How can I load a file into a TextBox or RichTextBox?

   Medium How can I make all the files in a directory uppercase or lowercase?

   Medium I have a program that writes to a file. Instead of adding to it, it overwrites it. What's wrong?

How can I check for the existance of files?

Compatibility:VB3 VB4 VB5

Use this function:

Public Function fileExist(fileName As String) As Boolean
    Dim l As Long
    
    On Error Resume Next
    
    l = FileLen(fileName)
    
    fileExist = Not (Err.Number > 0)
    
    On Error GoTo 0
End Function

I'm trying to read a file with EOF's in it. I can't read past the first EOF.

Compatibility:VB3 VB4 VB5

In VB, there are three modes of I/O. Random, Text, and Binary. When you open a file as Text mode, you are telling VB that the file you're reading is a text file. Text files end with a EOF. So, the answer would be to open the file as binary. Binary files can have EOFs in them with no problem. Instead of this:

open "myfile.dat" as #1 for input

Do this:

open "myfile.dat" as #1 for binaryNote that you will have to use slightly different functions in binary mode.

How can I load a file into a TextBox or RichTextBox?

Compatibility:VB3 VB4 VB5

Use the following code:

        dim sFile as string
        'Set sFile equal to your filename
        dim i as long
        
        i = freefile()
        
        open sFile for input as #i
                txtMain.text = input$(i,LOF(i))
        close #1

How can I make all the files in a directory uppercase or lowercase?

Compatibility:VB3 VB4 VB5

Say you want to take a whole bunch of files and make them all named in lowercase(or uppercase). Launch VB, and copy and paste this code:

Dim s As String, mypath As String

mypath = "d:\mydir\moredir"
  
s = Dir$(mypath & "*.txt")   '*.* works too
  
Do While s <> ""
  Name mypath & s As mypath & LCase$(s)
  s = Dir$()
Loop

I have a program that writes to a file. Instead of adding to it, it overwrites it. What's wrong?

Compatibility:VB3 VB4 VB5

When you open a file like this:

Open ... for output

You're telling VB to create a new file or overwrite the only one. What you want to say is:

open ... for append

That should solve your problem.

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