COM2PictureConverter.cs source code in C# .NET

                        Code:
                         / FX-1434 / FX-1434 / 1.0 / untmp / whidbey / REDBITS / ndp / fx / src / WinForms / Managed / System / WinForms / ComponentModel / COM2Interop / COM2PictureConverter.cs / 1 / COM2PictureConverter.cs
                        
                        
                            //------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//----------------------------------------------------------------------------- 

 
namespace System.Windows.Forms.ComponentModel.Com2Interop { 
    using System.Runtime.Serialization.Formatters;
    using System.ComponentModel; 
    using System.Diagnostics;
    using System;
    using System.Drawing;
    using System.Collections; 
    using Microsoft.Win32;
 
    ///  
    /// 
    /// This class maps an IPicture to a System.Drawing.Image. 
    /// 
    internal class Com2PictureConverter : Com2DataTypeToManagedDataTypeConverter {

        object lastManaged; 
        IntPtr lastNativeHandle;
        WeakReference pictureRef; 
        IntPtr lastPalette = IntPtr.Zero; 

        Type pictureType = typeof(Bitmap); 

        public Com2PictureConverter(Com2PropertyDescriptor pd) {
            if (pd.DISPID == NativeMethods.ActiveX.DISPID_MOUSEICON || pd.Name.IndexOf("Icon") != -1) {
                pictureType = typeof(Icon); 
            }
        } 
 
        /// 
        ///  
        ///     Returns the managed type that this editor maps the property type to.
        /// 
        public override Type ManagedType {
            get { 
                return pictureType;
            } 
        } 

        ///  
        /// 
        ///     Converts the native value into a managed value
        /// 
        public override object ConvertNativeToManaged(object nativeValue, Com2PropertyDescriptor pd) { 

            if (nativeValue == null) { 
                return null; 
            }
 
            Debug.Assert(nativeValue is UnsafeNativeMethods.IPicture, "nativevalue is not IPicture");

            UnsafeNativeMethods.IPicture nativePicture = (UnsafeNativeMethods.IPicture)nativeValue;
            IntPtr handle = nativePicture.GetHandle(); 

            if (lastManaged != null && handle == lastNativeHandle) { 
                return lastManaged; 
            }
 
            lastNativeHandle = handle;
            //lastPalette = nativePicture.GetHPal();
            if (handle != IntPtr.Zero) {
                switch (nativePicture.GetPictureType()) { 
                    case  NativeMethods.Ole.PICTYPE_ICON:
                        pictureType = typeof(Icon); 
                        lastManaged = Icon.FromHandle(handle); 
                        break;
                    case   NativeMethods.Ole.PICTYPE_BITMAP: 
                        pictureType = typeof(Bitmap);
                        lastManaged = Image.FromHbitmap(handle);
                        break;
                    default: 
                        Debug.Fail("Unknown picture type");
 			break; 
                } 
                pictureRef = new WeakReference(nativePicture);
            } 
            else {
                lastManaged = null;
                pictureRef = null;
            } 
            return lastManaged;
        } 
 
        /// 
        ///  
        ///     Converts the managed value into a native value
        /// 
        public override object ConvertManagedToNative(object managedValue, Com2PropertyDescriptor pd, ref bool cancelSet) {
            // don't cancel the set 
            cancelSet = false;
 
            if (lastManaged != null && lastManaged.Equals(managedValue) && pictureRef != null && pictureRef.IsAlive) { 
                return pictureRef.Target;
            } 

            // we have to build an IPicture
            lastManaged = managedValue;
 
            if (managedValue != null) {
                Guid g = typeof(UnsafeNativeMethods.IPicture).GUID; 
                NativeMethods.PICTDESC pictdesc = null; 
                bool own = false;
 
                if (lastManaged is Icon) {
                    pictdesc = NativeMethods.PICTDESC.CreateIconPICTDESC(((Icon)lastManaged).Handle);
                }
                else if (lastManaged is Bitmap) { 
                    pictdesc = NativeMethods.PICTDESC.CreateBitmapPICTDESC(((Bitmap)lastManaged).GetHbitmap(), lastPalette);
                    own = true; 
                } 
                else {
                    Debug.Fail("Unknown Image type: " + managedValue.GetType().Name); 
                }

                UnsafeNativeMethods.IPicture pict = UnsafeNativeMethods.OleCreatePictureIndirect(pictdesc, ref g, own);
                lastNativeHandle = pict.GetHandle(); 
                pictureRef = new WeakReference(pict);
                return pict; 
            } 
            else {
                lastManaged = null; 
                lastNativeHandle = lastPalette = IntPtr.Zero;
                pictureRef = null;
                return null;
            } 
        }
    } 
} 


// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
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COM2PictureConverter.cs source code in C# .NET

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