How to download and store an image using Windows.Web.Http? - c#

How do I download and store a jpeg image from the internet in a Windows Store App with Windows.Web.Http?
The problem that I am facing is that I don't know what Get…Async and Write…Async method I must use for an image? It is very different with files, than with strings.
Only Windows.Web.Http!
No third-party solutions!
If you suggest something else, please use the comment section, not the answer. Thank you!
…
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);

You can get a buffer using the GetBufferAsync method and then call the FileIO.WriteBufferAsync to write the buffer to a file:
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);

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;
}
}

This is a similar answer to John's, however in WP8.1 you can't use GetBufferAsync. Instead you can use GetStreamAsync in the way that I have:
Uri uri = new Uri(UriString);
string fileName = p4.IconLocation;
HttpClient client = new HttpClient();
var streamImage = await client.GetStreamAsync(uri);
await SaveToLocalFolderAsync(streamImage, fileName);
using the function:
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);
}
}

Related

How to convert an Image URL into a StorageFile?

I am working with Unsplash API to get Images. When I send the request for an Image, part of the answer is the Image URL which looks like this:
https://images.unsplash.com/photo-1535159530326-d7bf54bfb24e?ixlib=rb-0.3.5&q=85&fm=jpg&crop=entropy&cs=srgb&ixid=eyJhcHBfaWQiOjM1NDkzfQ&s
I was able to make this URL a BitmapImage and make it an Image Source in the app UI. But I was not able to download it to make it a StorageFile.
How can I download the image from this kind of URL and/or make it a StorageFile?
The following code will download the file into local storage, and then give you a Uri that you can use to set the Image Source:
private async Task<String> DownloadImage(string url, String fileName)
{
const String imagesSubdirectory = "DownloadedImages";
var rootFolder = await ApplicationData.Current.LocalFolder.CreateFolderAsync(imagesSubdirectory, CreationCollisionOption.OpenIfExists);
var storageFile = await rootFolder.CreateFileAsync(fileName, CreationCollisionOption.ReplaceExisting);
using (HttpClient client = new HttpClient())
{
byte[] buffer = await client.GetByteArrayAsync(url);
using (Stream stream = await storageFile.OpenStreamForWriteAsync())
stream.Write(buffer, 0, buffer.Length);
}
// Use this path to load image
String newPath = String.Format("ms-appdata:///local/{0}/{1}", imagesSubdirectory, fileName);
return newPath;
}
// Here is an example of how to use the new DownloadImage() method
private async void Button_Download(object sender, RoutedEventArgs e)
{
var uniqueFileName = $#"{Guid.NewGuid()}.jpg";
String newPath = await DownloadImage("https://images.unsplash.com/photo-1535159530326-d7bf54bfb24e?ixlib=rb-0.3.5&q=85&fm=jpg&crop=entropy&cs=srgb&ixid=eyJhcHBfaWQiOjM1NDkzfQ&s=6dbf8e03a25f469d0f845992e6b2eb9e",
uniqueFileName);
myImage.Source = new BitmapImage(new Uri(newPath));
}

Save recorded sound to project file in UWP

I recorded sound with the device's microphone but I don't know how to save it. Is it with the help of MediaCapture element, and if yes, then how to do it?
Here is a basic idea how to convert to mp3 and save in a file with Datawriter.
I wrote this code on the fly so its not tested.
MediaEncodingProfile _Profile = Windows.Media.MediaProperties.MediaEncodingProfile.CreateMp3(AudioEncodingQuality.High);
MediaTranscoder _Transcoder = new Windows.Media.Transcoding.MediaTranscoder();
CancellationTokenSource _cts = new CancellationTokenSource();
private void ConvertSteamToMp3()
{
IRandomAccessStream audio = buffer.CloneStream(); //your recoreded InMemoryRandomAccessStream
var folder = KnownFolders.MusicLibrary.CreateFolderAsync("MyCapturedAudio", CreationCollisionOption.OpenIfExists);
outputFile = await folder.CreateFileAsync("record.mp3", CreationCollisionOption.GenerateUniqueName);
using (IRandomAccessStream fileStream = await outputFile.OpenAsync(FileAccessMode.ReadWrite))
{
var preparedTranscodeResult = await _Transcoder.PrepareStreamTranscodeAsync(audio, fileStream, _Profile);
if (preparedTranscodeResult.CanTranscode)
{
var progress = new Progress<double>(TranscodeProgress);
await preparedTranscodeResult.TranscodeAsync().AsTask(_cts.Token, progress);
}
using (IOutputStream outputStream = fileStream.GetOutputStreamAt(0))
{
using (DataWriter dataWriter = new DataWriter(outputStream))
{
//TODO: Replace "Bytes" with the type you want to write.
dataWriter.WriteBytes(bytes);
await dataWriter.StoreAsync();
dataWriter.DetachStream();
}
await outputStream.FlushAsync();
}
}
}
Or just save the stream in a file
public async SaveToFile()
{
IRandomAccessStream audio = buffer.CloneStream(); //your recoreded InMemoryRandomAccessStream
var folder = KnownFolders.MusicLibrary.CreateFolderAsync("MyCapturedAudio", CreationCollisionOption.OpenIfExists);
outputFile = await folder.CreateFileAsync("record.mp3", CreationCollisionOption.GenerateUniqueName);
using (IRandomAccessStream fileStream = await outputFile.OpenAsync(FileAccessMode.ReadWrite))
{
await RandomAccessStream.CopyAndCloseAsync(audio.GetInputStreamAt(0), fileStream.GetOutputStreamAt(0));
await audio.FlushAsync();
audio.Dispose();
}
});
}

Save .mp4 to Windows Phone video library

I was wondering how I can download an MP4 video file from a URI and save it to the media library on Windows Phone 8.1.
It would be great if it worked in a Universal App - but it doesn't have to.
I found this code to save an image to the camera roll - do I go the same way about this with an *.mp4 to save it to the video library? And can I just hand off a download stream (not sure if that makes sense) to that function?
StorageFolder testFolder = await StorageFolder.GetFolderFromPathAsync(#"C:\test");
StorageFile sourceFile = await testFolder.GetFileAsync("TestImage.jpg");
StorageFile destinationFile = await KnownFolders.CameraRoll.CreateFileAsync("MyTestImage.jpg");
using (var sourceStream = await sourceFile.OpenReadAsync())
{
using (var sourceInputStream = sourceStream.GetInputStreamAt(0))
{
using (var destinationStream = await destinationFile.OpenAsync(FileAccessMode.ReadWrite))
{
using (var destinationOutputStream = destinationStream.GetOutputStreamAt(0))
{
await RandomAccessStream.CopyAndCloseAsync(sourceInputStream, destinationStream);
}
}
}
}
So I finally figured it out, this is what my code looks like:
var httpClient = new HttpClient();
var response = await httpClient.GetAsync(url);
if (response.IsSuccessStatusCode)
{
var file = await response.Content.ReadAsByteArrayAsync();
StorageFile destinationFile
= await KnownFolders.SavedPictures.CreateFileAsync("file.mp4",
CreationCollisionOption.ReplaceExisting);
Windows.Storage.Streams.IRandomAccessStream stream = await destinationFile.OpenAsync(FileAccessMode.ReadWrite);
IOutputStream output = stream.GetOutputStreamAt(0);
DataWriter writer = new DataWriter(output);
writer.WriteBytes(file);
await writer.StoreAsync();
await output.FlushAsync();
}

Download an image to local storage in Metro style apps

In WinRT / C#, How do I download an image to a local folder to support caching of an online catalogue for offline use? is there a way to directly download the images and link the control to get them from the cache as a fallback?
var downloadedimage = await HttpWebRequest.Create(url).GetResponseAsync();
StorageFile imgfile = await ApplicationData.Current.LocalFolder.CreateFileAsync(
"localfile.png", CreationCollisionOption.FailIfExists);
What do I do next to store downloadedimage as localfile.jpg?
Looks like the code below from the HttpClient sample for Windows 8 solves the issue
HttpRequestMessage request = new HttpRequestMessage(
HttpMethod.Get, resourceAddress);
HttpResponseMessage response = await rootPage.httpClient.SendAsync(request,
HttpCompletionOption.ResponseHeadersRead);
httpClient is a HttpClient, and its BaseAddress needs to be set a the server folder of your resource. we can then do this to convert that to an image source (if that's what we're downloading)
InMemoryRandomAccessStream randomAccessStream =
new InMemoryRandomAccessStream();
DataWriter writer = new DataWriter(randomAccessStream.GetOutputStreamAt(0));
writer.WriteBytes(await response.Content.ReadAsByteArrayAsync());
await writer.StoreAsync();
BitmapImage image = new BitmapImage();
imagecontrol.SetSource(randomAccessStream);
or this to write it to file
var imageFile = await ApplicationData.Current.LocalFolder.CreateFileAsync(
filename, CreationCollisionOption.ReplaceExisting);
var fs = await imageFile.OpenAsync(FileAccessMode.ReadWrite);
DataWriter writer = new DataWriter(fs.GetOutputStreamAt(0));
writer.WriteBytes(await response.Content.ReadAsByteArrayAsync());
await writer.StoreAsync();
writer.DetachStream();
await fs.FlushAsync();
Try this:
var response = await HttpWebRequest.Create(url).GetResponseAsync();
List<Byte> allBytes = new List<byte>();
using (Stream imageStream = response.GetResponseStream())
{
byte[] buffer = new byte[4000];
int bytesRead = 0;
while ((bytesRead = await imageStream.ReadAsync(buffer, 0, 4000)) > 0)
{
allBytes.AddRange(buffer.Take(bytesRead));
}
}
var file = await ApplicationData.Current.LocalFolder.CreateFileAsync(
"localfile.png", CreationCollisionOption.FailIfExists);
await FileIO.WriteBytesAsync(file, allBytes.ToArray());
If you want to download a file represented by a URL, the easiest way is to use the BackgroundDownloader class. See this page for more information on how to use the background downloader.
GetResponseAsync will give you a WebResponse file not the image:
Stream imageStream = downloadedimage.GetResponseStream();
Then you can write to the image file:
byte[] imageData = new byte[imageStream.Length];
using(StreamReader reader = new Streamreader(imageStream))
{
reader.ReadBytes(imageData, 0, imageData.Length);
}
await FileIO.WriteBytesAsync(imgfile, imageData);
By default Bitmap Images are cached by WinRT with no intervention required by the developer.

Write (Read) IO.Stream to (from) ApplicationData.Current.LocalFolder

What is the best way to read amnd write and IO.Stream (Zip file downloded from internet in my case) to ApplicationData.Current.LocalFolder
I tried
public static async Task WriteToFile(
this System.IO.Stream input,
string fileName,
StorageFolder folder = null)
{
folder = folder ?? ApplicationData.Current.LocalFolder;
var file = await folder.CreateFileAsync(
fileName,
CreationCollisionOption.ReplaceExisting);
using (var fs = await file.OpenAsync(FileAccessMode.ReadWrite))
{
using (var outStream = fs.GetOutputStreamAt(0))
{
using (var dataWriter = new DataWriter(outStream))
{
byte[] buffer = new byte[8 * 1024];
int len;
while ((len = input.Read(buffer, 0, buffer.Length)) > 0)
{
dataWriter.WriteBytes(buffer);
}
await dataWriter.StoreAsync();
dataWriter.DetachStream();
}
await outStream.FlushAsync();
}
}
}
for writing and
StorageFile file = await ApplicationData.Current.LocalFolder.GetFileAsync(filename);
var fileStream = await file.OpenAsync(Windows.Storage.FileAccessMode.Read);
var stream = fileStream.AsStreamForRead();
but the file gets corrupted somewhere along the way.I do no think there is a problem with reading so it should be somewhere in writing the file. Is there a better way to write IO.Stream to ApplicationData.Current.LocalFolder that works?
Try this:
static async void DownloadFileAsync(
this HttpClient httpClient,
string requestUri,
string fileName,
StorageFolder folder = null)
{
folder = folder ?? ApplicationData.Current.LocalFolder;
var file = await folder.CreateFileAsync(
fileName, CreationCollisionOption.ReplaceExisting);
using (var httpStream = await httpClient.GetStreamAsync(uri))
using (var fileStream = await file.OpenAsync(FileAccessMode.ReadWrite))
{
await httpStream.CopyToAsync(fileStream.AsStreamForWrite());
}
}
MSDN: Http­Client Class, Http­Client.­Get­Stream­Async Method, Windows­Runtime­Stream­Extensions.­As­Stream­For­Write Method, Stream.­Copy­To­Async Method.

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