WPF Image动态加载图片终极办法

//Createsource BitmapImagemyBitmapImage= new BitmapImage(); 
//BitmapImage.UriSourcemustbeinaBeginInit/EndInitblock 
myBitmapImage.BeginInit(); myBitmapImage.UriSource= new 
Uri(str,UriKind.Absolute); 
//Tosavesignificantapplicationmemory,settheDecodePixelWid

// Create source   
BitmapImage myBitmapImage = new BitmapImage();   
   
   
// BitmapImage.UriSource must be in a BeginInit/EndInit block   
myBitmapImage.BeginInit();   
myBitmapImage.UriSource = new Uri(str, UriKind.Absolute);   
   
   
// To save significant application memory, set the DecodePixelWidth or     
// DecodePixelHeight of the BitmapImage value of the image source to the desired    
// height or width of the rendered image. If you don't do this, the application will    
// cache the image as though it were rendered as its normal size rather then just    
// the size that is displayed.   
// Note: In order to preserve aspect ratio, set DecodePixelWidth   
// or DecodePixelHeight but not both.   
myBitmapImage.DecodePixelWidth = 2048;   
myBitmapImage.EndInit();   
//set image source   


Image img = new Image(); 
img.Source = myBitmapImage;

// Create source   
BitmapImage myBitmapImage = new BitmapImage();   
   
   
// BitmapImage.UriSource must be in a BeginInit/EndInit block   
myBitmapImage.BeginInit();   
myBitmapImage.UriSource = new Uri(str, UriKind.Absolute);   
   
   
// To save significant application memory, set the DecodePixelWidth or     
// DecodePixelHeight of the BitmapImage value of the image source to the desired    
// height or width of the rendered image. If you don't do this, the application will    
// cache the image as though it were rendered as its normal size rather then just    
// the size that is displayed.   
// Note: In order to preserve aspect ratio, set DecodePixelWidth   
// or DecodePixelHeight but not both.   
myBitmapImage.DecodePixelWidth = 2048;   
myBitmapImage.EndInit();   
//set image source   


Image img = new Image(); 
img.Source = myBitmapImage;