In my Silverlight control, I am loading my background image from a stream:
BitmapImage img = new BitmapImage();
img.SetSource(stream);
Image background = new Image();
background.Source = img;
How can I find out the height of the bitmap image that was loaded from stream? None of the usual suspects (e.g., Property, DependencyProperty) seem to be available, neither on img, nor on background.
I would try:
img.Measure();
img.DesiredSize.Height;
Related
I know how to convert bitmap into BitmapImage from Load a WPF BitmapImage from a System.Drawing.Bitmap
But when my bitmap is changing, and I wanna the source of image, i.e. the BitmapImage will change with the bitmap in real time, how can I do it?
My code for generating bitmap is like this:
Rectangle rect = new Rectangle(0, 0, 300, 300);
bitmap = new Bitmap(rect.Width, rect.Height);
Graphics g = Graphics.FromImage(bitmap);
DoWithGraphics(g, rect, pictureelements);
DoWithGraphics is a series of g.FillRectangle
Thanks!
It shouldn't be a problem to display the bitmap in an Image control and update the Source property whenever the bitmap changes.
I have two assemblies, say assembly1 and assembly2.
In assembly2 there is a XAML file. In this XAML file I want to create an image.
What I want to do is setting the source of this image to a bitmap that is in a resx file from assembly1.
<Image Name="image1" Stretch="Fill" Source="???" />
How do I correctly reference to that bitmap file in XAML? Is there an easy "XAML-only" solution?
Okay, so I assume there is no thing such as an "XAML-only" solution.
Instead, I do it like this after the WPF control's Loaded event is called:
Assembly coreAssembly = Assembly.GetAssembly(typeof (otherAssembly.Resources));
var resourceManager = new ResourceManager("otherAssembly.Resources", coreAssembly);
// get image from core resources
Bitmap completeImage = (Bitmap) resourceManager.GetObject("Complete");
// apply image to WPF image
var memoryStream = new MemoryStream();
completeImage.Save(memoryStream, System.Drawing.Imaging.ImageFormat.Png);
BitmapImage bitmapImage = new BitmapImage();
bitmapImage.BeginInit();
bitmapImage.StreamSource = new MemoryStream(memoryStream.ToArray());
bitmapImage.EndInit();
this.myWpfImage.Source = bitmapImage;
i dont have a problem with binding a bitmapimage to image tag in codebehind for eg.
BitmapImage image = new BitmapImage();
imagetaginxaml.Source = image; // this will remove whatever image is currently on the image tag in xaml and attach the empty bitmapimage above
but i'm not able to get the image by doing the reverse, for example, i want to process the image that is currently on the image tag. i am not able to do this
BitmapImage image = imagetaginxaml.Source;
what should i do
Well, Image.Source is of type ImageSource, there is no quarantee that it will be a BitmapImage, it may be though. If the source is created by the XAML parser it will be a BitmapFrameDecode (which is an internal class). Anyway, the only save assignment is:
ImageSource source = img.Source;
otherwise you need to cast:
BitmapImage source = (BitmapImage)img.Source;
which will throw an exception if the Source is not of this type. So you can either save-cast or try-catch:
//(Possibly check for img.Source != null first)
BitmapImage source = img.Source as BitmapImage;
if (source != null)
{
//If img.Source is not null the cast worked.
}
try
{
BitmapImage source = (BitmapImage)img.Source;
//If this line is reached it worked.
}
catch (Exception)
{
//Cast failed
}
You could also check the type beforehand using img.SourceisBitmapImage.
How about using WriteableBitmap to make a copy of the image, and then using a MemoryStream to copy the original image into a copy?
// Create a WriteableBitmap from the Image control
WriteableBitmap bmp = new WriteableBitmap(imagetaginxaml, null);
// Load the contents of a MemoryStream from the WritableBitmap
MemoryStream m = new MemoryStream();
bmp.SaveJpeg(m, bmp.PixelWidth, bmp.PixelHeight, 0, 100);
// Read from the stream into a new BitmapImage object
m.Position = 0;
BitmapImage image = new BitmapImage();
image.SetSource(m);
// do something with the new BitmapImage object
// (for example, load another image control)
anotherimagetaginxaml.Source = image;
This is a simple Question (lets see)
I want to bind bitmap image to Image. For doing this in cs code u must write this line.
this.leftImage.Source = new BitmapImage(new Uri(#"C:\a.bmp"));
But I want make Binding from resources. Because In release time resources became part of project.exe file and if you make binding from file(Mean set Image.source with Image file address), you must always put image file in the same address(disaster programing) :)
One option is to get it from a resx file. You can do something similar to this. Assuming Images.resx contains a Left image bitmap.
leftImage.Source = ConvertBitmapToBitmapImage(Images.Left);
...
private BitmapImage ConvertBitmapToBitmapImage(Bitmap bitmap)
{
MemoryStream memoryStream = new MemoryStream();
bitmap.Save(memoryStream, ImageFormat.Png);
BitmapImage bitmapImage = new BitmapImage();
bitmapImage.BeginInit();
bitmapImage.StreamSource = new MemoryStream(memoryStream.ToArray());
bitmapImage.EndInit();
return bitmapImage;
}
With some more work, you can do this from XAML too.
I have this code in Silverlight:
Image image = new Image();
BitmapImage bitmapImage= TheDatasourceManager.GetBitmapImage("blackPencil");
image.Source = bitmapImage;
image.Stretch = Stretch.None;
image.HorizontalAlignment = HorizontalAlignment.Left;
image.VerticalAlignment = VerticalAlignment.Top;
image.Margin = new Thickness(88, 88, 0, 0);
grid.Children.Add(image);
Now I want to find out the height of the image.
in WPF I can get it with image.Source.Height but this is not available in Silverlight
bitmapImage.Height doesn't exist either
when I debug and examine the image object, I eventually get to PixelHeight which has an accurate height, but I can't seem to access it
I find image.ActualHeight but it is 0.
How can I get the height of the image?
I finally found it, it's just bitmapImage.PixelHeight. Since I'm not stretching it, seems to work fine.