VarEnum Enum

Reference

Definition

Namespace:: System.Runtime.InteropServices

Assembly:: System.Runtime.InteropServices.dll

Assembly:: mscorlib.dll

Assembly:: netstandard.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Caution

Marshalling VARIANTs may be unavailable in future releases.

Indicates how to marshal the array elements when an array is marshaled from managed to unmanaged code as a SafeArray.

public enum class VarEnum

[System.Obsolete("Marshalling VARIANTs may be unavailable in future releases.")]
public enum VarEnum

public enum VarEnum

[System.Serializable]
public enum VarEnum

[System.Serializable]
[System.Runtime.InteropServices.ComVisible(true)]
public enum VarEnum

[<System.Obsolete("Marshalling VARIANTs may be unavailable in future releases.")>]
type VarEnum =

type VarEnum =

[<System.Serializable>]
type VarEnum =

[<System.Serializable>]
[<System.Runtime.InteropServices.ComVisible(true)>]
type VarEnum =

Public Enum VarEnum

Inheritance: Object

ValueType

Enum
VarEnum

Attributes: ObsoleteAttribute SerializableAttribute ComVisibleAttribute

Fields

VT_ARRAY	8192	Indicates a `SAFEARRAY` pointer.
VT_BLOB	65	Indicates length prefixed bytes.
VT_BLOB_OBJECT	70	Indicates that a blob contains an object.
VT_BOOL	11	Indicates a Boolean value.
VT_BSTR	8	Indicates a BSTR string.
VT_BYREF	16384	Indicates that a value is a reference.
VT_CARRAY	28	Indicates a C style array.
VT_CF	71	Indicates the clipboard format.
VT_CLSID	72	Indicates a class ID.
VT_CY	6	Indicates a currency value.
VT_DATE	7	Indicates a DATE value.
VT_DECIMAL	14	Indicates a `decimal` value.
VT_DISPATCH	9	Indicates an `IDispatch` pointer.
VT_EMPTY	0	Indicates that a value was not specified.
VT_ERROR	10	Indicates an SCODE.
VT_FILETIME	64	Indicates a FILETIME value.
VT_HRESULT	25	Indicates an HRESULT.
VT_I1	16	Indicates a `char` value.
VT_I2	2	Indicates a `short` integer.
VT_I4	3	Indicates a `long` integer.
VT_I8	20	Indicates a 64-bit integer.
VT_INT	22	Indicates an integer value.
VT_LPSTR	30	Indicates a null-terminated string.
VT_LPWSTR	31	Indicates a wide string terminated by `null`.
VT_NULL	1	Indicates a null value, similar to a null value in SQL.
VT_PTR	26	Indicates a pointer type.
VT_R4	4	Indicates a `float` value.
VT_R8	5	Indicates a `double` value.
VT_RECORD	36	Indicates a user defined type.
VT_SAFEARRAY	27	Indicates a SAFEARRAY. Not valid in a VARIANT.
VT_STORAGE	67	Indicates that the name of a storage follows.
VT_STORED_OBJECT	69	Indicates that a storage contains an object.
VT_STREAM	66	Indicates that the name of a stream follows.
VT_STREAMED_OBJECT	68	Indicates that a stream contains an object.
VT_UI1	17	Indicates a `byte`.
VT_UI2	18	Indicates an `unsignedshort`.
VT_UI4	19	Indicates an `unsignedlong`.
VT_UI8	21	Indicates an 64-bit unsigned integer.
VT_UINT	23	Indicates an `unsigned` integer value.
VT_UNKNOWN	13	Indicates an `IUnknown` pointer.
VT_USERDEFINED	29	Indicates a user defined type.
VT_VARIANT	12	Indicates a VARIANT `far` pointer.
VT_VECTOR	4096	Indicates a simple, counted array.
VT_VOID	24	Indicates a C style `void`.

Examples

using namespace System;
using namespace System::Runtime::InteropServices;

// If you do not have a type library for an interface
// you can redeclare it using ComImportAttribute.
// This is how the interface would look in an idl file.
//[
//object,
//uuid("73EB4AF8-BE9C-4b49-B3A4-24F4FF657B26"),
//dual, helpstring("IMyStorage Interface"),
//pointer_default(unique)
//]
//interface IMyStorage : IDispatch
//{
// [id(1)]
// HRESULT GetItem([in] BSTR bstrName, [out, retval] IDispatch ** ppItem);
// [id(2)]
// HRESULT GetItems([in] BSTR bstrLocation, [out] SAFEARRAY(VARIANT)* pItems);
// [id(3)]
// HRESULT GetItemDescriptions([in] BSTR bstrLocation, [out] SAFEARRAY(VARIANT) ** ppItems);
// [id(4), propget]
// HRESULT get_IsEmpty([out, retval] BOOL * pfEmpty);
//};
// This is the managed declaration.

[ComImport]
[Guid("73EB4AF8-BE9C-4b49-B3A4-24F4FF657B26")]
interface class IMyStorage
{
   [DispId(1)]
   Object^ GetItem( [In,MarshalAs(UnmanagedType::BStr)]String^ bstrName );

   //[return : MarshalAs(UnmanagedType::Interface)]

   [DispId(2)]
   void GetItems( [In,MarshalAs(UnmanagedType::BStr)]String^ bstrLocation, [Out,MarshalAs(UnmanagedType::SafeArray,
   SafeArraySubType=VarEnum::VT_VARIANT)]array<Object^>^Items );

   [DispId(3)]
   void GetItemDescriptions( [In]String^ bstrLocation, [In,Out,MarshalAs(UnmanagedType::SafeArray)]array<Object^>^varDescriptions );

   property bool IsEmpty 
   {
      [DispId(4)]
      [returnvalue:MarshalAs(UnmanagedType::VariantBool)]
      bool get();
   }
};

using System;
using System.Runtime.InteropServices;

namespace MyModule
{
    // If you do not have a type library for an interface
    // you can redeclare it using ComImportAttribute.

    // This is how the interface would look in an idl file.

    //[
    //object,
    //uuid("73EB4AF8-BE9C-4b49-B3A4-24F4FF657B26"),
    //dual,	helpstring("IMyStorage Interface"),
    //pointer_default(unique)
    //]
    //interface IMyStorage : IDispatch
    //{
    //	[id(1)]
    //	HRESULT GetItem([in] BSTR bstrName, [out, retval] IDispatch ** ppItem);
    //	[id(2)]
    //	HRESULT GetItems([in] BSTR bstrLocation, [out] SAFEARRAY(VARIANT)* pItems);
    //	[id(3)]
    //	HRESULT GetItemDescriptions([in] BSTR bstrLocation, [out] SAFEARRAY(VARIANT) ** ppItems);
    //	[id(4), propget]
    //	HRESULT get_IsEmpty([out, retval] BOOL * pfEmpty);
    //};

    // This is the managed declaration.

    [ComImport]
    [Guid("73EB4AF8-BE9C-4b49-B3A4-24F4FF657B26")]
    public interface IMyStorage
    {
        [DispId(1)]
        [return : MarshalAs( UnmanagedType.Interface )]
        Object GetItem( [In, MarshalAs( UnmanagedType.BStr )] String bstrName );

        [DispId(2)]
        void GetItems( [In, MarshalAs( UnmanagedType.BStr )] String bstrLocation,
            [Out, MarshalAs( UnmanagedType.SafeArray,
                      SafeArraySubType = VarEnum.VT_VARIANT )] out Object[] Items );

        [DispId(3)]
        void GetItemDescriptions( [In] String bstrLocation,
            [In, Out, MarshalAs( UnmanagedType.SafeArray )] ref Object[] varDescriptions );

        bool IsEmpty
        {
            [DispId(4)]
            [return : MarshalAs( UnmanagedType.VariantBool )]
            get;
        }
    }
}

Imports System.Runtime.InteropServices

Module MyModule
    ' If you do not have a type library for an interface
    ' you can redeclare it using ComImportAttribute.

    ' This is how the interface would look in an idl file.

    '[
    'object,
    'uuid("73EB4AF8-BE9C-4b49-B3A4-24F4FF657B26"),
    'dual,	helpstring("IMyStorage Interface"),
    'pointer_default(unique)
    ']
    'interface IMyStorage : IDispatch
    '{
    '	[id(1)]
    '	HRESULT GetItem([in] BSTR bstrName, [out, retval] IDispatch ** ppItem);
    '	[id(2)]
    '	HRESULT GetItems([in] BSTR bstrLocation, [out] SAFEARRAY(VARIANT)* pItems);
    '	[id(3)]
    '	HRESULT GetItemDescriptions([in] BSTR bstrLocation, [out] SAFEARRAY(VARIANT) ** ppItems);
    '	[id(4), propget]
    '	HRESULT get_IsEmpty([out, retval] BOOL * pfEmpty);
    '};

    ' This is the managed declaration.

    <ComImport(), Guid("73EB4AF8-BE9C-4b49-B3A4-24F4FF657B26")> _
    Public Interface IMyStorage
        <DispId(1)> _
        Function GetItem(<InAttribute(), MarshalAs(UnmanagedType.BStr)> ByVal bstrName As String) _
           As <MarshalAs(UnmanagedType.Interface)> Object

        <DispId(2)> _
        Function GetItems(<InAttribute(), MarshalAs(UnmanagedType.BStr)> ByVal bstrLocation As String, _
           <OutAttribute(), MarshalAs(UnmanagedType.SafeArray, SafeArraySubType := VarEnum.VT_VARIANT)> _
                                      ByVal Items() As Object)

        <DispId(3)> _
        Function GetItemDescriptions(<InAttribute()> ByVal bstrLocation As String, _
           <InAttribute(), OutAttribute(), _
                      MarshalAs(UnmanagedType.SafeArray)> ByRef varDescriptions() As Object)

        <DispId(4)> _
        ReadOnly Property IsEmpty(<MarshalAs(UnmanagedType.VariantBool)> ByVal bEmpty As Boolean)

    End Interface
End Module

Remarks

Used with System.Runtime.InteropServices.MarshalAsAttribute to explicitly control the element type of the SafeArray.

Applies to