如何投下控制的IOleObject(How to cast a control to IOleObj

我想要调用GetClientSite在.NET控件。 为此我想投一个控件的IOleObject返回空值（例如Windows.Forms.Form中）。

我应该怎么做才能得到的IOleObject？

using System;
using System.Runtime.InteropServices;
using System.Security;
using System.Windows.Forms;

namespace Test001
{
    public class Form001 : Form
    {
        public Form001()
        {
            InitializeComponent();
        }

        private void InitializeComponent()
        {
            this.SuspendLayout();
            this.Name = "Form001";
            this.Text = "Form001";
            this.Load += new System.EventHandler(this.Form001_Load);
            this.ResumeLayout(false);
        }

        private void Form001_Load(object sender, EventArgs e)
        {
            IOleObject obj = (IOleObject) this;
            //IOleClientSite site = obj.GetClientSite();
        }
    }

    [ComImport, Guid("00000112-0000-0000-C000-000000000046"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown), SuppressUnmanagedCodeSecurity]
    public interface IOleObject
    {
        [PreserveSig]
        int SetClientSite([In, MarshalAs(UnmanagedType.Interface)] IOleClientSite pClientSite);
        IOleClientSite GetClientSite();
        [PreserveSig]
        int SetHostNames([In, MarshalAs(UnmanagedType.LPWStr)] string szContainerApp, [In, MarshalAs(UnmanagedType.LPWStr)] string szContainerObj);
        [PreserveSig]
        int Close(int dwSaveOption);
        [PreserveSig]
        int SetMoniker([In, MarshalAs(UnmanagedType.U4)] int dwWhichMoniker, [In, MarshalAs(UnmanagedType.Interface)] object pmk);
        [PreserveSig]
        int GetMoniker([In, MarshalAs(UnmanagedType.U4)] int dwAssign, [In, MarshalAs(UnmanagedType.U4)] int dwWhichMoniker, [MarshalAs(UnmanagedType.Interface)] out object moniker);
        [PreserveSig]
        int InitFromData([In, MarshalAs(UnmanagedType.Interface)] IDataObject pDataObject, int fCreation, [In, MarshalAs(UnmanagedType.U4)] int dwReserved);
        [PreserveSig]
        int GetClipboardData([In, MarshalAs(UnmanagedType.U4)] int dwReserved, out IDataObject data);
        [PreserveSig]
        int DoVerb(int iVerb, [In] IntPtr lpmsg, [In, MarshalAs(UnmanagedType.Interface)] IOleClientSite pActiveSite, int lindex, IntPtr hwndParent, [In] object lprcPosRect);
        [PreserveSig]
        int EnumVerbs(out object e);
        [PreserveSig]
        int OleUpdate();
        [PreserveSig]
        int IsUpToDate();
        [PreserveSig]
        int GetUserClassID([In, Out] ref Guid pClsid);
        [PreserveSig]
        int GetUserType([In, MarshalAs(UnmanagedType.U4)] int dwFormOfType, [MarshalAs(UnmanagedType.LPWStr)] out string userType);
        [PreserveSig]
        int SetExtent([In, MarshalAs(UnmanagedType.U4)] int dwDrawAspect, [In] object pSizel);
        [PreserveSig]
        int GetExtent([In, MarshalAs(UnmanagedType.U4)] int dwDrawAspect, [Out] object pSizel);
        [PreserveSig]
        int Advise(object pAdvSink, out int cookie);
        [PreserveSig]
        int Unadvise([In, MarshalAs(UnmanagedType.U4)] int dwConnection);
        [PreserveSig]
        int EnumAdvise(out object e);
        [PreserveSig]
        int GetMiscStatus([In, MarshalAs(UnmanagedType.U4)] int dwAspect, out int misc);
        [PreserveSig]
        int SetColorScheme([In] object pLogpal);
    }

    [ComImport, InterfaceType(ComInterfaceType.InterfaceIsIUnknown), Guid("00000118-0000-0000-C000-000000000046")]
    public interface IOleClientSite
    {
        [PreserveSig]
        int SaveObject();
        [PreserveSig]
        int GetMoniker([In, MarshalAs(UnmanagedType.U4)] int dwAssign, [In, MarshalAs(UnmanagedType.U4)] int dwWhichMoniker, [MarshalAs(UnmanagedType.Interface)] out object moniker);
        [PreserveSig]
        int GetContainer(out object container);
        [PreserveSig]
        int ShowObject();
        [PreserveSig]
        int OnShowWindow(int fShow);
        [PreserveSig]
        int RequestNewObjectLayout();
    }
}

Answer 1:

所述IOleObject接口是内部内部嵌套接口UnsafeNativeMethods在类System.Windows.Forms组件。 该System.Windows.Forms.Control 内部实现它，并明确 。

创建具有相同的名称和GUID另一个接口不会使其“在同一界面”上的管理水平。

这条线

IOleObject obj = (IOleObject) this;

代表管理.NET铸造，并没有任何与COM。 该投将只从的WinForms组件，这是不公开的确切相同的接口。

你可以尝试使用反射通过InterfaceMapping结构而获得方法（但请注意，这是不推荐）：

Type thisType = this.GetType();

Type oleInterface = thisType.GetInterface("IOleObject");

MethodInfo getSiteMethod = oleInterface.GetMethod("GetClientSite");

//InterfaceMapping is used to get more complex interface scenarios
InterfaceMapping map = thisType.GetInterfaceMap(oleInterface);

//at which index is the explicit implementation
int index = Array.IndexOf(map.InterfaceMethods, getSiteMethod);
MethodInfo actualExplicitMethod = map.TargetMethods[index];

//late-bound call (slow)
object o = actualExplicitMethod.Invoke(this, new object[] { });

现在，第一个，你会得到一个内部类型包裹在System.Object不能投你的接口，因为原来的接口是内部的，所以你能有更多的乐趣与思考，只要你打算使用该对象。

第二，我已经试过了，技术是可行的，但在特定情况下这种方法称为Windows窗体上抛出一个异常- "Top-level Windows Forms control cannot be exposed as an ActiveX control." 。

Answer 2:

我用这个方法：

IOleClientSite pClientSite = (IOleClientSite)Site.GetService(new AntiMoniker().GetType());

定义AntiMoniker的例子。 现在，不需要细节。 刚刚获得系统.__ ComObject的实例。

[ComImport(), Guid("00000305-0000-0000-C000-000000000046")]
class AntiMoniker {
}

它会在.NET Framework 2.0中/ IE8 / WinXP的SP3工作

谢谢

Answer 3:

这是另一种方法 ，使用Marshal.CreateAggregatedObject去私人COM接口。

文章来源: How to cast a control to IOleObject