下面是一个动态设置映像路径的例子(映像位于磁盘上的某个位置，而不是作为资源构建):

if (File.Exists(imagePath))
{
    // Create image element to set as icon on the menu element
    Image icon = new Image();
    BitmapImage bmImage = new BitmapImage();
    bmImage.BeginInit();
    bmImage.UriSource = new Uri(imagePath, UriKind.Absolute);
    bmImage.EndInit();
    icon.Source = bmImage;
    icon.MaxWidth = 25;
    item.Icon = icon;
}

关于图标的思考……

首先，您可能认为Icon属性只能包含图像。但它实际上可以包含任何东西!当我试图通过编程方式将Image属性直接设置为包含图像路径的字符串时，我偶然发现了这一点。结果是它没有显示图像，而是显示路径的实际文本!

这导致了一种不必为图标制作图像的替代方案，而是使用带有符号字体的文本来显示简单的“图标”。下面的例子使用了包含“软盘”符号的Wingdings字体。这个符号实际上是字符<，它在XAML中有特殊的含义，所以我们必须使用编码版本&lt;代替。这就像做梦一样!下面将软盘符号显示为菜单项上的图标:

<MenuItem Name="mnuFileSave" Header="Save" Command="ApplicationCommands.Save">
  <MenuItem.Icon>
    <Label VerticalAlignment="Center" HorizontalAlignment="Center" FontFamily="Wingdings">&lt;</Label>
  </MenuItem.Icon>
</MenuItem>

在遇到与您相同的问题并进行了一些阅读之后，我发现了解决方案—打包uri。

我在代码中做了以下事情:

Image finalImage = new Image();
finalImage.Width = 80;
...
BitmapImage logo = new BitmapImage();
logo.BeginInit();
logo.UriSource = new Uri("pack://application:,,,/AssemblyName;component/Resources/logo.png");
logo.EndInit();
...
finalImage.Source = logo;

或者更短，通过使用另一个BitmapImage构造函数:

finalImage.Source = new BitmapImage(
    new Uri("pack://application:,,,/AssemblyName;component/Resources/logo.png"));

URI被分成几个部分:

Authority: application:/// Path: The name of a resource file that is compiled into a referenced assembly. The path must conform to the following format: AssemblyShortName[;Version][;PublicKey];component/Path AssemblyShortName: the short name for the referenced assembly. ;Version [optional]: the version of the referenced assembly that contains the resource file. This is used when two or more referenced assemblies with the same short name are loaded. ;PublicKey [optional]: the public key that was used to sign the referenced assembly. This is used when two or more referenced assemblies with the same short name are loaded. ;component: specifies that the assembly being referred to is referenced from the local assembly. /Path: the name of the resource file, including its path, relative to the root of the referenced assembly's project folder.

application:后面的三个斜杠必须用逗号代替:

注意:包URI的授权组件 是一个嵌入式URI，指向 包装，必须符合RFC 2396。 此外，“/”字符必须 替换为“，”字符， 以及保留字符，如“%” "?"必须转义。查看OPC 获取详细信息。

当然，还要确保将映像上的构建操作设置为Resource。

这是我的方式:

internal static class ResourceAccessor
{
    public static Uri Get(string resourcePath)
    {
        var uri = string.Format(
            "pack://application:,,,/{0};component/{1}"
            , Assembly.GetExecutingAssembly().GetName().Name
            , resourcePath
        );

        return new Uri(uri);
    }
}

用法:

new BitmapImage(ResourceAccessor.Get("Images/1.png"))

你有没有试过:

Assembly asm = Assembly.GetExecutingAssembly();
Stream iconStream = asm.GetManifestResourceStream("SomeImage.png");
BitmapImage bitmap = new BitmapImage();
bitmap.BeginInit();
bitmap.StreamSource = iconStream;
bitmap.EndInit();
_icon.Source = bitmap;

如果你已经有了一个流，并且知道它的格式，你可以使用这样的东西:

static ImageSource PngStreamToImageSource (Stream pngStream) {
    var decoder = new PngBitmapDecoder(pngStream,
        BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
    return decoder.Frames[0];
}

将框架放在VisualBrush中:

VisualBrush brush = new VisualBrush { TileMode = TileMode.None };

brush.Visual = frame;

brush.AlignmentX = AlignmentX.Center;
brush.AlignmentY = AlignmentY.Center;
brush.Stretch = Stretch.Uniform;

把VisualBrush放在几何绘图中

GeometryDrawing drawing = new GeometryDrawing();

drawing.Brush = brush;

// Brush this in 1, 1 ratio
RectangleGeometry rect = new RectangleGeometry { Rect = new Rect(0, 0, 1, 1) };
drawing.Geometry = rect;

现在将几何绘图放在DrawingImage中:

new DrawingImage(drawing);

把这个放在你的图片源上，然后是voilà!

你可以做得更简单:

<Image>
    <Image.Source>
        <BitmapImage UriSource="/yourassembly;component/YourImage.PNG"></BitmapImage>
    </Image.Source>
</Image>

在代码中:

BitmapImage image = new BitmapImage { UriSource="/yourassembly;component/YourImage.PNG" };