保存图像到媒体库在Windows Phone 7

Question

我想从我的应用程序主页中的图像控件名为image1保存图像到手机的媒体库这里是我的代码，但在WriteableBitmap wr = image1;它给了我一个错误。

public void SaveImageTo(string fileName = "Gage.jpg") 
{ 
    fileName += ".jpg"; 
    var myStore = IsolatedStorageFile.GetUserStoreForApplication(); 
    if (myStore.FileExists(fileName)) 
    { 
     myStore.DeleteFile(fileName); 
    } 

    IsolatedStorageFileStream myFileStream = myStore.CreateFile(fileName); 
    WriteableBitmap wr = image1; // give the image source 
    wr.SaveJpeg(myFileStream, wr.PixelWidth, wr.PixelHeight, 0, 85); 
    myFileStream.Close(); 

    // Create a new stream from isolated storage, and save the JPEG file to the        media library on Windows Phone. 
    myFileStream = myStore.OpenFile(fileName, FileMode.Open, FileAccess.Read); 
    MediaLibrary library = new MediaLibrary(); 
    //byte[] buffer = ToByteArray(qrImage); 
    library.SavePicture(fileName, myFileStream); } 

Answer 1

您正试图将Control“图像1”分配给WriteableBitmap对象，这就是为什么你有一个错误（它们是两种不同类型的）。

您应根据“image1”的来源设置不同来初始化WriteableBitmap。

如果“图像1”引用了本地图像，可以初始化相应的WriteableBitmap这样：

BitmapImage img = new BitmapImage(new Uri(@"images/yourimage.jpg", UriKind.Relative)); 
img.CreateOptions = BitmapCreateOptions.None; 
img.ImageOpened += (s, e) => 
{ 
    WriteableBitmap wr = new WriteableBitmap((BitmapImage)s); 
}; 

如果你想渲染图像控制到一个WriteableBitmap的，你可以这样做：

WriteableBitmap wr = new WriteableBitmap(image1, null);