VB & VBA in a Nutshell: The Language

FileAttr Function

Named Arguments

Yes

Syntax

FileAttr(filenumber, [returntype])

filenumber

Use: Required

Data Type: Integer

Any valid file number.

returntype

Use: Required

Data Type: Integer

An optional number specifying the information to return; if you omit the argument, its value defaults to 1.

Return Value

If you specify a returntype of 1, the file access mode is returned as a long integer, as shown in the following table:

Mode	Value
Input	1
Output	2
Random	4
Append	8
Binary	32

Description

Determines the file access mode for a file opened using the Open statement. When used on a 16-bit Windows system, FileAttr can also obtain an operating-system file handle.

Rules at a Glance

• Use a returntype of 1 to obtain a return value that indicates the mode in which the file was opened.

• On 16-bit Windows systems only, use a returntype of 2 to obtain an operating system file handle for the file.

Programming Tips and Gotchas

• File handles—the numbers by which files are identified by the operating system—are assigned by the operating system. In contrast, the application-defined file number used in the Open statement or returned by the FreeFile function is simply a pointer into an internal table of file handles maintained by Visual Basic. In other words, the file number that references a file in a 16-bit Visual Basic program is really a pseudo-handle that is local to the program. By calling the FileAttr function with a returnvalue of 2, you can obtain the systemwide file handle. This ...