在 WPF 图像中显示图标

Question

I have a WPF application that needs to extract the icon off of an executable.

I found here that I can do this

Icon ico = Icon.ExtractAssociatedIcon(theProcess.MainModule.FileName);

but when I try to set the source of a WPF Image I get

"Cannot implicitly convert type 'System.Drawing.Icon' to 'System.Windows.Media.ImageSource'

Any suggestions ?

Answer 1

System.Windows.Interop.Imaging.CreateBitmapSourceFromHIcon method can be use to convert a System.Drawing.Icon to wpf BitmapSource .

using(Icon ico = Icon.ExtractAssociatedIcon(theProcess.MainModule.FileName))
{
    image.Source = Imaging.CreateBitmapSourceFromHIcon(ico.Handle, Int32Rect.Empty, BitmapSizeOptions.FromEmptyOptions());
}

Answer 2

Icons get no love in the .NET framework. You'll have to use Icon.Save() to save the icon you got into a MemoryStream. Which allows you to use the IconBitmapDecoder constructor that takes a stream.

Answer 3

I wanted to offer the solution I've come up with:

public static class IconExtensions
{
    [DllImport("gdi32.dll", SetLastError = true)]
    private static extern bool DeleteObject(IntPtr hObject);


    public static ImageSource ToImageSource(this Icon icon)
    {
        Bitmap bitmap = icon.ToBitmap();
        IntPtr hBitmap = bitmap.GetHbitmap();

        ImageSource wpfBitmap = Imaging.CreateBitmapSourceFromHBitmap(
            hBitmap,
            IntPtr.Zero,
            Int32Rect.Empty,
            BitmapSizeOptions.FromEmptyOptions());

        if (!DeleteObject(hBitmap))
        {
            throw new Win32Exception();
        }

        return wpfBitmap;
    }

}

I then have a IconToImageSourceConverter that simply calls the method above.

To make it easy for me to add icons as images I also added this:

<DataTemplate DataType="{x:Type drawing:Icon}">
    <Image Source="{Binding Converter={converter:IconToImageSourceConverter}}" 
        MaxWidth="{Binding Width}" MaxHeight="{Binding Height}"/>
</DataTemplate>

This way, if an icon is placed directly in XAML if will still be shown:

<x:Static MemberType="{x:Type drawing:SystemIcons}" Member="Asterisk"/>

Otherwise the converter can be used on location, like so:

<Image Source="{Binding Source={x:Static drawing:SystemIcons.Asterisk}, 
    Converter={converter:IconToImageSourceConverter}}"/>                

Answer 4

I had a similar problem and in few steps we can get the image source:

ImageSource imageSource;

Icon icon = Icon.ExtractAssociatedIcon(path);

using (Bitmap bmp = icon.ToBitmap())
{
   var stream = new MemoryStream();
   bmp.Save(stream, System.Drawing.Imaging.ImageFormat.Png);
   imageSource = BitmapFrame.Create(stream);
}

We can use this image source to feed the property source in out XAML:

 <Image Source="{Binding Path=ImageSource, Mode=OneTime}" />

Answer 5

I use this extension method to convert from Icon to ImageSource:

public static System.Windows.Media.ImageSource ToWpfImageSource(this System.Drawing.Icon icon)
{
   using (MemoryStream strm = new MemoryStream())
   {
        icon.Save(strm);
        return System.Windows.Media.Imaging.BitmapFrame.Create(strm, System.Windows.Media.Imaging.BitmapCreateOptions.None, System.Windows.Media.Imaging.BitmapCacheOption.OnLoad);    
   }    
}

...

Icon icon = Icon.ExtractAssociatedIcon(path);
ImageSouce imageWpf = icon.ToWpfImageSource();