ComImportAttribute 类

定义

指示该属性化类型是以前在 COM 中定义的。Indicates that the attributed type was previously defined in COM.

public ref class ComImportAttribute sealed : Attribute
[System.AttributeUsage(System.AttributeTargets.Class | System.AttributeTargets.Interface, Inherited=false)]
[System.Runtime.InteropServices.ComVisible(true)]
public sealed class ComImportAttribute : Attribute
type ComImportAttribute = class
    inherit Attribute
Public NotInheritable Class ComImportAttribute
Inherits Attribute
继承
ComImportAttribute
属性

示例

下面的示例演示如何将应用ComImportAttribute于托管接口声明。The following example demonstrates how to apply the ComImportAttribute to a managed interface declaration. 仅当在源代码中手动生成互操作程序集, 并想要模拟 Tlbimp.exe 生成的元数据时, 才应用此特性。You apply this attribute only when generating an interop assembly manually in source code, and want to simulate the metadata produced by Tlbimp.exe.

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

注解

您可以将此特性应用于类或接口, 尽管tlbimp.exe (类型库导入程序)通常会在导入类型库时为您应用此特性。You can apply this attribute to classes or interfaces, although the Tlbimp.exe (Type Library Importer) typically applies it for you when it imports a type library.

ComImportAttribute是一个伪自定义属性, 指示类型已在以前发布的类型库中定义。ComImportAttribute is a pseudo-custom attribute that indicates that a type has been defined in a previously published type library. 当激活、导出、强制等操作时, 公共语言运行时将以不同方式处理这些类型。The common language runtime treats these types differently when activating, exporting, coercing, and so on.

备注

托管对象继承的所有基本 COM 类型都必须聚合自由线程封送拆收器 (INTERNAL.H)。All base COM types that are inherited by a managed object must aggregate the Free Threaded Marshaler (FTM). 不聚合 INTERNAL.H 的 COM 类型不能由托管对象继承。COM types that do not aggregate the FTM can't be inherited by managed objects.

构造函数

ComImportAttribute()

初始化 ComImportAttribute 的新实例。Initializes a new instance of the ComImportAttribute.

属性

TypeId

在派生类中实现时,获取此 Attribute 的唯一标识符。When implemented in a derived class, gets a unique identifier for this Attribute.

(继承自 Attribute)

方法

Equals(Object)

返回一个值,该值指示此实例是否与指定的对象相等。Returns a value that indicates whether this instance is equal to a specified object.

(继承自 Attribute)
GetHashCode()

返回此实例的哈希代码。Returns the hash code for this instance.

(继承自 Attribute)
GetType()

获取当前实例的 TypeGets the Type of the current instance.

(继承自 Object)
IsDefaultAttribute()

在派生类中重写时,指示此实例的值是否是派生类的默认值。When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class.

(继承自 Attribute)
Match(Object)

当在派生类中重写时,返回一个指示此实例是否等于指定对象的值。When overridden in a derived class, returns a value that indicates whether this instance equals a specified object.

(继承自 Attribute)
MemberwiseClone()

创建当前 Object 的浅表副本。Creates a shallow copy of the current Object.

(继承自 Object)
ToString()

返回一个表示当前对象的 string。Returns a string that represents the current object.

(继承自 Object)

显式界面实现

_Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr)

将一组名称映射为对应的一组调度标识符。Maps a set of names to a corresponding set of dispatch identifiers.

(继承自 Attribute)
_Attribute.GetTypeInfo(UInt32, UInt32, IntPtr)

检索对象的类型信息,然后可以使用该信息获取接口的类型信息。Retrieves the type information for an object, which can be used to get the type information for an interface.

(继承自 Attribute)
_Attribute.GetTypeInfoCount(UInt32)

检索对象提供的类型信息接口的数量(0 或 1)。Retrieves the number of type information interfaces that an object provides (either 0 or 1).

(继承自 Attribute)
_Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

提供对某一对象公开的属性和方法的访问。Provides access to properties and methods exposed by an object.

(继承自 Attribute)

适用于

另请参阅