Skip to Content
VB.NET Language in a Nutshell, Second Edition
book

VB.NET Language in a Nutshell, Second Edition

by Steven Roman PhD, Ron Petrusha, Paul Lomax
April 2002
Intermediate to advanced
688 pages
19h 51m
English
O'Reilly Media, Inc.
Content preview from VB.NET Language in a Nutshell, Second Edition

Name

Loc Function

Class

Microsoft.VisualBasic.FileSystem

Syntax

Loc(filenumber)
filenumber (required; Integer)

Any valid file number

Return Value

A Long indicating the current position of the read/write pointer in a file

Description

Determines the current position of the file read/write pointer

Rules at a Glance

  • If you have opened the file in Random mode, Loc returns the record number of the last record read or written.

  • If you have opened the file in Input or Output modes (sequential), Loc returns the current byte position in the file divided by 128.

  • If you have opened the file in Binary mode, Loc returns the position of the last byte read or written.

Example

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

  • For sequential files, the return value of Loc is not required and should not be used.

  • Note that you cannot set the position of the file pointer using Loc.

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Start your free trial

You might also like

VB .NET Language in a Nutshell

VB .NET Language in a Nutshell

Steven Roman PhD, Ron Petrusha, Paul Lomax

Publisher Resources

ISBN: 0596003080Supplemental ContentCatalog PageErrata