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FileSystem.Loc(Int32) Method

  • Reference

Definition

Namespace:
Microsoft.VisualBasic
Assembly:
Microsoft.VisualBasic.Core.dll
Assembly:
Microsoft.VisualBasic.dll
Source:
FileSystem.vb
Source:
FileSystem.vb
Source:
FileSystem.vb

Returns a value that specifies the current read/write position in an open file.

public:
 static long Loc(int FileNumber);
public static long Loc (int FileNumber);
static member Loc : int -> int64
Public Function Loc (FileNumber As Integer) As Long

Parameters

FileNumber
Int32

Required. Any valid Integer file number.

Returns

Int64

The current read/write position in an open file.

Exceptions

IOException

File mode is invalid.

Examples

This example uses the Loc function to return the current read/write position in an open file. This example assumes that MyFile is a text file that has several lines of sample data.

Dim location As Long
Dim oneChar As Char
FileOpen(1, "C:\TESTFILE.TXT", OpenMode.Binary)
While location < LOF(1)
    Input(1, oneChar)
    location = Loc(1)
    WriteLine(1, location & ControlChars.CrLf)
End While
FileClose(1)

Remarks

The Loc function is zero-based; using it to retrieve the first byte in a file will return 0.

The Loc function is provided for backward compatibility and may affect performance. For non-legacy applications, the My.Computer.FileSystem object provides better performance. For more information, see File Access with Visual Basic.

The following describes the return value for each file access mode:

Mode Return value
Random Number of the last record read from or written to the file.
Sequential Current byte position in the file divided by 128. However, information returned by Loc for sequential files is neither used nor required.
Binary Position of the last byte read or written.

Applies to

See also