ComImportAttribute 类

定义

命名空间:

System.Runtime.InteropServices

程序集:

System.Runtime.InteropServices.dll

指示先前在 COM 中定义的特性化类型。

public ref class ComImportAttribute sealed : Attribute

[System.AttributeUsage(System.AttributeTargets.Class | System.AttributeTargets.Interface, Inherited=false)]
public sealed class ComImportAttribute : Attribute

[<System.AttributeUsage(System.AttributeTargets.Class | System.AttributeTargets.Interface, Inherited=false)>]
type ComImportAttribute = class
    inherit Attribute

Public NotInheritable Class ComImportAttribute
Inherits Attribute

继承

Object

Attribute

ComImportAttribute

属性

AttributeUsageAttribute

示例

以下示例演示如何将 应用于 ComImportAttribute 托管接口声明。 仅当在源代码中手动生成互操作程序集，并且想要模拟 Tlbimp.exe 生成的元数据时，才应用此属性。

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

可以将此属性应用于类或接口，但 Tlbimp.exe (类型库导入程序) 通常会在导入类型库时应用此属性。

ComImportAttribute 是一个伪自定义属性，指示已在以前发布的类型库中定义了类型。 公共语言运行时在激活、导出、强制等操作时以不同的方式对待这些类型。

注意

托管对象继承的所有基 COM 类型都必须聚合自由线程封送收器 (FTM) 。 不聚合 FTM 的 COM 类型不能由托管对象继承。

构造函数

ComImportAttribute()

初始化 ComImportAttribute 的新实例。

属性

TypeId

在派生类中实现时，获取此 Attribute 的唯一标识符。 (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。 (继承自 Attribute)
GetHashCode()	返回此实例的哈希代码。 (继承自 Attribute)
GetType()	获取当前实例的 Type。 (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。 (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。 (继承自 Attribute)
MemberwiseClone()	创建当前 Object 的浅表副本。 (继承自 Object)
ToString()	返回表示当前对象的字符串。 (继承自 Object)

另请参阅

• Tlbimp.exe（类型库导入程序）