c# - 在 c# wpf 中从 Memorystream 获取图像源

Question

如何使用 c#ImageSource从MemoryStreamWPF 中获取？或转换MemoryStream为ImageSource在 wpf 中将其显示为图像？

Answer 1

using (MemoryStream memoryStream = ...)
{
    var imageSource = new BitmapImage();
    imageSource.BeginInit();
    imageSource.StreamSource = memoryStream;
    imageSource.EndInit();

    // Assign the Source property of your image
    image.Source = imageSource;
}

Answer 2

如果您在分配给任何内容之前处置了流，则除了@Darin Dimitrov 答案之外，Image.Source将显示任何内容，所以要小心

例如，Next 方法将不起作用，From one of my projects using LiteDB

public async Task<BitmapImage> DownloadImage(string id)
{
    using (var stream = new MemoryStream())
    {
        var f = _appDbManager.DataStorage.FindById(id);
        f.CopyTo(stream);
        var imageSource = new BitmapImage {CacheOption = BitmapCacheOption.OnLoad};
        imageSource.BeginInit();
        imageSource.StreamSource = stream;
        imageSource.EndInit();
        return imageSource;
    }
}

你不能使用imageSource从最后一个函数返回的

但是这个实现会起作用

public async Task<BitmapImage> DownloadImage(string id)
{
    // TODO: [Note] Bug due to memory leaks, if we used Using( var stream = new MemoryStream()), we will lost the stream, and nothing will shown
    var stream = new MemoryStream();
    var f = _appDbManager.DataStorage.FindById(id);
    f.CopyTo(stream);
    var imageSource = new BitmapImage {CacheOption = BitmapCacheOption.OnLoad};
    imageSource.BeginInit();
    imageSource.StreamSource = stream;
    imageSource.EndInit();
    return imageSource;
}