WPF图像在运行时动态更改图像源

Question

我有一个标题窗口.当用户从下拉列表中选择一个选项时,标题图像可以改变.问题是当图像加载时,它是模糊的,拉伸的和像素化的.这些是我正在使用的PNG文件,它们在动态设置源之前看起来很好.

这是我用来更改图像源代码的代码.

string strUri2 = String.Format(@"pack://application:,,,/MyAssembly;component/resources/main titles/{0}", CurrenSelection.TitleImage);
Stream iconStream2 = App.GetResourceStream(new Uri(strUri2)).Stream;
imgTitle.Source = HelperFunctions.returnImage(iconStream2);

这是辅助函数.

    public static BitmapImage returnImage(Stream iconStream)
    {
        Bitmap brush = new Bitmap(iconStream);
        System.Drawing.Image img = brush.GetThumbnailImage(brush.Height, brush.Width, null, System.IntPtr.Zero);
        var imgbrush = new BitmapImage();
        imgbrush.BeginInit();
        imgbrush.StreamSource = ConvertImageToMemoryStream(img);
        imgbrush.CreateOptions = BitmapCreateOptions.PreservePixelFormat;
        imgbrush.EndInit();
        var ib = new ImageBrush(imgbrush);
        return imgbrush;
    }

    public static MemoryStream ConvertImageToMemoryStream(System.Drawing.Image img)
    {
        var ms = new MemoryStream();
        img.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
        return ms;
    }

和XAML

            <Image x:Name="imgTitle" HorizontalAlignment="Left" VerticalAlignment="Bottom" Grid.Column="1" Grid.Row="1" Stretch="None" d:IsLocked="False"/>

对于参考:

xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 

任何人有任何想法是什么？

Answer 1

我可以想到两件事:

首先,尝试加载图像:

string strUri2 = String.Format(@"pack://application:,,,/MyAseemby;component/resources/main titles/{0}", CurrenSelection.TitleImage);
imgTitle.Source = new BitmapImage(new Uri(strUri2));

也许问题是WinForm的图像调整大小,如果图像被拉伸,将图像控件上的Stretch设置为"Uniform"或"UnfirofmToFill".

第二个选项是图像可能没有与像素网格对齐,您可以在我的博客上阅读它:http://www.nbdtech.com/blog/archive/2008/11/20/blurred-images-in- wpf.aspx

Answer 2

嘿,这个有点丑,但它只是一行:

imgTitle.Source = new BitmapImage(new Uri(@"pack://application:,,,/YourAssembly;component/your_image.png"));