如何使用Windows.Web.Http在Windows应用商店应用中从互联网下载和存储jpeg图像?
我面临的问题是,我不知道Get ... Async和Write ...我必须使用异步方法来处理图像吗?它与文件非常不同,而不是字符串。
仅限Windows.Web.Http !
没有第三方解决方案!
如果您提出其他建议,请使用评论部分,而不是答案。谢谢!
…
using Windows.Storage;
using Windows.Web.Http;
Uri uri = new Uri("http://image.tmdb.org/t/p/w300/" + posterPath);
HttpClient httpClient = new HttpClient();
// I guess I need to use one of the Get...Async methods?
var image = await httpClient.Get…Async(uri);
StorageFolder localFolder = ApplicationData.Current.LocalFolder;
StorageFolder cachedPostersFolder = await localFolder.CreateFolderAsync("cached posters", CreationCollisionOption.OpenIfExists);
StorageFile posterFile = await cachedPostersFolder.CreateFileAsync(posterPath, CreationCollisionOption.ReplaceExisting);
// I guess I need to use one of the Write...Async methods?
await FileIO.Write…Async(posterFile, image);
答案 0 :(得分:6)
您可以使用GetBufferAsync
方法获取缓冲区,然后调用FileIO.WriteBufferAsync
将缓冲区写入文件:
Uri uri = new Uri("http://i.stack.imgur.com/ZfLdV.png?s=128&g=1");
string fileName = "daniel2.png";
StorageFile destinationFile = await KnownFolders.PicturesLibrary.CreateFileAsync(
fileName, CreationCollisionOption.GenerateUniqueName);
HttpClient client = new HttpClient();
var buffer = await client.GetBufferAsync(uri);
await Windows.Storage.FileIO.WriteBufferAsync(destinationFile, buffer);
答案 1 :(得分:1)
image1.Source = new BitmapImage(new Uri("http://www.image.com/image.jpg", UriKind.RelativeOrAbsolute));
using (var mediaLibrary = new MediaLibrary())
{
using (var stream = new MemoryStream())
{
var fileName = string.Format("Gs{0}.jpg", Guid.NewGuid());
bmp.SaveJpeg(stream, bmp.PixelWidth, bmp.PixelHeight, 0, 100);
stream.Seek(0, SeekOrigin.Begin);
var picture = mediaLibrary.SavePicture(fileName, stream);
if (picture.Name.Contains(fileName)) return true;
}
}
答案 2 :(得分:1)
这是John的类似答案,但是在WP8.1中你不能使用GetBufferAsync。相反,你可以像我一样使用GetStreamAsync:
Uri uri = new Uri(UriString);
string fileName = p4.IconLocation;
HttpClient client = new HttpClient();
var streamImage = await client.GetStreamAsync(uri);
await SaveToLocalFolderAsync(streamImage, fileName);
使用函数:
public async Task SaveToLocalFolderAsync(Stream file, string fileName)
{
StorageFolder localFolder = ApplicationData.Current.LocalFolder;
StorageFile storageFile = await localFolder.CreateFileAsync(fileName, CreationCollisionOption.ReplaceExisting);
using (Stream outputStream = await storageFile.OpenStreamForWriteAsync())
{
await file.CopyToAsync(outputStream);
}
}