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VBFixedArrayAttribute Class

Indicates that an array in a structure or non-local variable should be treated as a fixed-length array.

<System.AttributeUsage(System.AttributeTargets.Field, _
   Inherited := False, AllowMultiple := False)> _
Public NotInheritable Class VBFixedArrayAttribute
   Inherits System.Attribute

Visual Basic arrays are of variable length by default. This attribute is useful when using Visual Basic file input and output functions, such as FileGet and FilePut, and API calls that require fixed-length arrays.

Structure Book
    <VBFixedArray(4)> Public Chapter() As Integer 
End Structure 

Sub WriteData()
    Dim FileNum As Integer = FreeFile()
    Dim MyBook As Book
    ReDim MyBook.Chapter(4)
    ' Add code to populate the array.
    MyBook.Chapter(0) = 1
    MyBook.Chapter(1) = 2
    MyBook.Chapter(2) = 3
    MyBook.Chapter(3) = 4
    MyBook.Chapter(4) = 5
    ' Write the array to a file.
    FileOpen(FileNum, "C:\testfile", OpenMode.Binary, _
             OpenAccess.Write, OpenShare.Default)
    FilePut(FileNum, MyBook) ' Write data.
End Sub

The VBFixedArrayAttribute is informational and does not allocate any storage. The purpose of this attribute is to modify how arrays in structures and non-local variables are used by methods or API calls that recognize the VBFixedArrayAttribute. Keep in mind that this attribute does not convert a variable length array to a fixed array and that you must still allocate array storage using Dim or ReDim statements.

Namespace: Microsoft.VisualBasic

Assembly: Visual Basic Runtime Library (in Microsoft.VisualBasic.dll)