webbrowser 实现IOleControl接口2

using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Forms;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Globalization;
namespace GetCode
{
    public class MyWebBrowser : WebBrowser
    {
        private const int DISPID_AMBIENT_DLCONTROL = -5512;
        private int _downloadControlFlags;

        // we want our site class, not the default one
        protected override WebBrowserSiteBase CreateWebBrowserSiteBase()
        {
            return new MyWebBrowserSite(this);
        }

        [DispId(DISPID_AMBIENT_DLCONTROL)]
        public int DownloadControlFlags
        {
            get
            {
                return _downloadControlFlags;
            }
            set
            {
                if (_downloadControlFlags == value)
                    return;

                _downloadControlFlags = value;
                IOleControl ctl = (IOleControl)ActiveXInstance;
                ctl.OnAmbientPropertyChange(DISPID_AMBIENT_DLCONTROL);
            }
        }

        protected class MyWebBrowserSite : WebBrowserSite, IReflect
        {
            private Dictionary<int, PropertyInfo> _dispidCache;
            private MyWebBrowser _host;

            public MyWebBrowserSite(MyWebBrowser host)
                : base(host)
            {
                _host = host;
            }

            object IReflect.InvokeMember(string name, BindingFlags invokeAttr, Binder binder, object target, object[] args, ParameterModifier[] modifiers, CultureInfo culture, string[] namedParameters)
            {
                object ret = null;
                // Check direct IDispatch call using a dispid (see http://msdn.microsoft.com/en-us/library/de3dhzwy.aspx)
                const string dispidToken = "[DISPID=";
                if (name.StartsWith(dispidToken))
                {
                    int dispid = int.Parse(name.Substring(dispidToken.Length, name.Length - dispidToken.Length - 1));
                    if (_dispidCache == null)
                    {
                        // WebBrowser has many properties, so we build a dispid cache on it
                        _dispidCache = new Dictionary<int, PropertyInfo>();
                        foreach (PropertyInfo pi in _host.GetType().GetProperties(BindingFlags.Public | BindingFlags.Instance))
                        {
                            if ((!pi.CanRead) || (pi.GetIndexParameters().Length > 0))
                                continue;

                            object[] atts = pi.GetCustomAttributes(typeof(DispIdAttribute), true);
                            if ((atts != null) && (atts.Length > 0))
                            {
                                DispIdAttribute da = (DispIdAttribute)atts[0];
                                _dispidCache[da.Value] = pi;
                            }
                        }
                    }

                    PropertyInfo property;
                    if (_dispidCache.TryGetValue(dispid, out property))
                    {
                        ret = property.GetValue(_host, null);
                    }
                }
                return ret;
            }

            FieldInfo[] IReflect.GetFields(BindingFlags bindingAttr)
            {
                return GetType().GetFields(bindingAttr);
            }

            MethodInfo[] IReflect.GetMethods(BindingFlags bindingAttr)
            {
                return GetType().GetMethods(bindingAttr);
            }

            PropertyInfo[] IReflect.GetProperties(BindingFlags bindingAttr)
            {
                return GetType().GetProperties(bindingAttr);
            }

            FieldInfo IReflect.GetField(string name, BindingFlags bindingAttr)
            {
                throw new NotImplementedException();
            }

            MemberInfo[] IReflect.GetMember(string name, BindingFlags bindingAttr)
            {
                throw new NotImplementedException();
            }

            MemberInfo[] IReflect.GetMembers(BindingFlags bindingAttr)
            {
                throw new NotImplementedException();
            }

            MethodInfo IReflect.GetMethod(string name, BindingFlags bindingAttr)
            {
                throw new NotImplementedException();
            }

            MethodInfo IReflect.GetMethod(string name, BindingFlags bindingAttr, Binder binder, Type[] types, ParameterModifier[] modifiers)
            {
                throw new NotImplementedException();
            }

            PropertyInfo IReflect.GetProperty(string name, BindingFlags bindingAttr, Binder binder, Type returnType, Type[] types, ParameterModifier[] modifiers)
            {
                throw new NotImplementedException();
            }

            PropertyInfo IReflect.GetProperty(string name, BindingFlags bindingAttr)
            {
                throw new NotImplementedException();
            }

            Type IReflect.UnderlyingSystemType
            {
                get { throw new NotImplementedException(); }
            }
        }

        [ComImport, InterfaceType(ComInterfaceType.InterfaceIsIUnknown), Guid("B196B288-BAB4-101A-B69C-00AA00341D07")]
        internal interface IOleControl
        {
            void Reserved0();
            void Reserved1();
            void OnAmbientPropertyChange(int dispID);
            void Reserved2();
        }
    }

    [Flags]
    public enum WebBrowserDownloadControlFlags : uint
    {
        DLIMAGES = 0x00000010,
        VIDEOS = 0x00000020,
        BGSOUNDS = 0x00000040,
        NO_SCRIPTS = 0x00000080,
        NO_JAVA = 0x00000100,
        NO_RUNACTIVEXCTLS = 0x00000200,
        NO_DLACTIVEXCTLS = 0x00000400,
        DOWNLOADONLY = 0x00000800,
        NO_FRAMEDOWNLOAD = 0x00001000,
        RESYNCHRONIZE = 0x00002000,
        PRAGMA_NO_CACHE = 0x00004000,
        NO_BEHAVIORS = 0x00008000,
        NO_METACHARSET = 0x00010000,
        URL_ENCODING_DISABLE_UTF8 = 0x00020000,
        URL_ENCODING_ENABLE_UTF8 = 0x00040000,
        NOFRAMES = 0x00080000,
        FORCEOFFLINE = 0x10000000,
        NO_CLIENTPULL = 0x20000000,
        SILENT = 0x40000000,
        OFFLINEIFNOTCONNECTED = 0x80000000,
        OFFLINE = OFFLINEIFNOTCONNECTED,
    }
}

调用代码

public partial class Form1:Form
{
    private MyWebBrowser _webBrowser;

    public Form1()
    {
        InitializeComponent();

        _webBrowser =newMyWebBrowser();
        _webBrowser.Dock=DockStyle.Fill;

        Controls.Add(_webBrowser);
    }

    private void button1_Click(object sender,EventArgs e)
    {
        _webBrowser.DownloadControlFlags=(int)WebBrowserDownloadControlFlags.DOWNLOADONLY;
        _webBrowser.Navigate("http://mysamplewebsite");
    }
}