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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.


Namespace:  Microsoft.VisualBasic
Assembly:  Microsoft.VisualBasic (in Microsoft.VisualBasic.dll)

[AttributeUsageAttribute(AttributeTargets::Field, Inherited = false, AllowMultiple = false)]
public ref class VBFixedArrayAttribute sealed : public Attribute

The VBFixedArrayAttribute type exposes the following members.

Public methodVBFixedArrayAttribute(Int32)Initializes the value of the Bounds property.
Public methodVBFixedArrayAttribute(Int32, Int32)Initializes the value of the Bounds property.

Public propertyBoundsReturns the bounds of the array.
Public propertyLengthReturns the size of the array.
Public propertyTypeIdWhen implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute.)

Public methodEqualsInfrastructure. Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute.)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetHashCodeReturns the hash code for this instance. (Inherited from Attribute.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodIsDefaultAttributeWhen overridden in a derived class, indicates whether the value of this instance is the default value for the derived class. (Inherited from Attribute.)
Public methodMatchWhen overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)

Explicit interface implemetationPrivate method_Attribute::GetIDsOfNamesMaps a set of names to a corresponding set of dispatch identifiers. (Inherited from Attribute.)
Explicit interface implemetationPrivate method_Attribute::GetTypeInfoRetrieves the type information for an object, which can be used to get the type information for an interface. (Inherited from Attribute.)
Explicit interface implemetationPrivate method_Attribute::GetTypeInfoCountRetrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from Attribute.)
Explicit interface implemetationPrivate method_Attribute::InvokeProvides access to properties and methods exposed by an object. (Inherited from 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.

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.