ComImportAttribute 类  
定义
重要
一些信息与预发行产品相关,相应产品在发行之前可能会进行重大修改。 对于此处提供的信息,Microsoft 不作任何明示或暗示的担保。
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)]
[System.Runtime.InteropServices.ComVisible(true)]
public sealed class ComImportAttribute : Attribute[<System.AttributeUsage(System.AttributeTargets.Class | System.AttributeTargets.Interface, Inherited=false)>]
type ComImportAttribute = class
    inherit Attribute[<System.AttributeUsage(System.AttributeTargets.Class | System.AttributeTargets.Interface, Inherited=false)>]
[<System.Runtime.InteropServices.ComVisible(true)>]
type ComImportAttribute = class
    inherit AttributePublic NotInheritable Class ComImportAttribute
Inherits Attribute- 继承
- 属性
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) | 
显式接口实现
| _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。(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。(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)。(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。(继承自 Attribute) |