VB.NET Language in a Nutshell, Second Edition

Name

LOF Function

Class

Microsoft.VisualBasic.FileSystem

Syntax

LOF(filenumber)

filenumber (required; Integer)

Any valid file number

Return Value

Long Integer

Description

Returns the size of an open file in bytes

Rules at a Glance

filenumber must be the number of a file opened using the FileOpen function.

Example

The following example shows how to use the LOF function to prevent reading past the end of a file in binary mode:

Dim fr As Integer = FreeFile(  )
Dim sChar As Char
FileOpen(fr, "c:\data.txt", OpenMode.Binary, OpenAccess.Read)

Do While Loc(fr) < LOF(fr)
    FileGet(fr, sChar)
    Debug.Write(Loc(fr) & ": ")
    Console.WriteLine(sChar)
Loop

Programming Tips and Gotchas

LOF works only on an open file; if you need to know the size of a file that isn’t open, use the FileLen function.

See Also

FileLen Function, FileOpen Procedure