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c# WPF URI syntax

I am just learning c# and have been struggling to work with URIs in WPF. I've googled around a fair bit but not having much luck.
Essentially I'm trying to have a BitmapImage object stored as a property in a Car object. I then want to display the BitmapImage in an Image control on a WPF form.
The app is a simple app (it's for a Uni assignment), so no database, etc.
I have two methods of doing this. The first is that I'm preloading Car data from a text file, including the filename of the JPG I want to load. I have included the JPG in a directory called Files which is off the main directory where my source code and class files are. I have set the JPG file to 'Content' and 'Always copy'. When I run a Debug, it copies the Files directory and the JPG to the debug\bin directory.
My code creates a BitmapImage by referring to the JPG using a URI as follows;
BitmapImage myImage = new BitmapImage (new Uri("Files/" + Car.Imagefilename, UriKind.Relative);
Car.Image = myImage;
ImageControl.Source = myImage;
If I step through this code in the debugger, it sometimes works and displays the image, but most of the time it doesn't.
My second method is when a user creates a new Car. This method always works. In this one, I use a file dialog box (dlg) to select the image and use an absolute path.
BitmapImage myImage = new BitmapImage (new Uri(dlg.Filename, UriKind.Absolute);
Car.Image = myImage;
ImageControl.Source = myImage;
So....I can't work out why the first method doesn't work. I think it's got something to do with the relative reference, but I can't work out how to syntax that properly to work. I've tried using "pack:,,,", I've tried adding "component", I've tried an '#' before the "pack". I can't seem to find something that explains this simply.
Apologies if this is straight forward but it's doing my head in! Appreciate any pointers.

If the image files are located in a "Files" folder of your Visual Studio project, you should set their Build Action to Resource (and Copy to Output Directory to Do not copy), and load them by a Resource File Pack URI:
var image = new BitmapImage(new Uri("pack://application:,,,/Files/" + Car.Imagefilename));
Car.Image = image;
ImageControl.Source = image;
There is no need to copy the files anywhere. Images are loaded directly from the assembly.

First try to load the image file using its absolute path. For example if the images are stored in c:\projects\yourproject\files, then try using something like
BitmapImage myImage = new BitmapImage (new Uri("c:/projects/yourproject/files/carname.jpg", UriKind.Absolute);
If it works, what you are facing is an path calculation issue.
At this point you may either calculate the Absolute with reference to your executable using AppDomain.CurrentDomain.BaseDirectory at runtime or use App.Config to store the path and reference it from there.
Cheers

Prism embedded image

I have a module called xModule. I have an image inside it marked as embedded resource.
Inside the initialization of the module I tried :
string stFileName = "SmallIcon.png";
string stAssembly = "xModule"; // That's the full name of the assembly
//img.BeginInit();
Uri uri = new Uri(String.Format(#"/{0};component/Images/{1}", stAssembly , stFileName),
UriKind.Relative);
ImageSource imgSource = new BitmapImage(uri);
During it's coming to the breakpoint on the ImageSource imgSource =.. line, it seems the ImageSource can't find the image...
Why? What's wrong with it?
I get no errors, the assembly is referenced. I did something similar in the Xaml and it worked.
Also used : VS11, Unity

I think you need to mark the image as "ressource" not "embedded ressource" ( WPF )
also See : What's the difference between a Resource and an Embedded Resource in a C# application?

C# - WPF how to unreference a BitmapImage so I can delete the source file?

This seems like a fairly simple issue, but I can't seem to figure a way to work around it.
In a WPF window I have an image, image_small_pic. In the associated C# file I set the value of that using this code:
Uri src = new Uri(image_source, UriKind.RelativeOrAbsolute);
small_image_bmp = new BitmapImage(src);
image_small_pic.Source = small_image_bmp;
Where small_image_bmp is a public BitmapImage object. But then if then, later on, if I change small_image_bmp to another file and reassign image_small_pic.Source, then the original image is still locked and I can't delete it. Even if I try later it's still locked. Any thoughts how I can free this up?

Check out this article. There's some odd behaviour with WPF images that you're coming across. The solution is to read in the bytes yourself and then create an image based on them, since if you let the framework handle it, the file will remain locked.

Uri src = new Uri(image_source, UriKind.RelativeOrAbsolute);
var small_image_bmp = new BitmapImage();
small_image_bmp.BeginInit();
small_image_bmp.CacheOption = BitmapCacheOption.OnLoad;
small_image_bmp.UriSource = src;
small_image_bmp.EndInit();
image_small_pic.Source = small_image_bmp;

Does WriteableBitmap has new features in Silverlight 4?

and if someone could give me an example on how to use it, with a stream? (not sure how that works) I know how to create a BitmapImage from an URI now I need to convert this image to a WriteableBitmap, but I get a null exception error with something like this:
BitmapImage image = new BitmapImage(new Uri("http://www.example.com/example.png"));
WriteableBitmap newImage = new WriteableBitmap(image);

In short: Nope, there are no new features in Silverlight 4. The WriteableBitmapEx tries to compensate the missing functionality.
Regarding your real problem:
You should add a handler to the BitmapImage.ImageFailed event to see if there's an error when the image should be downloaded. And you you should create the WriteableBitmap in the ImageOpened event handler.
var image = new BitmapImage(new Uri("http://www.example.com/example.png"));
WriteableBitmap newImage = null;
image.ImageOpened += (s, e) => newImage = new WriteableBitmap(image);
Please also note that cross-domain references are permitted. See the MSDN page for details. You should put the image into the Web Project's ClientBin folder and use a relative path instead.
As an alternative you can also compile the image into the assembly as resource and load it from there. The WriteableBitmapEx has an extension method to make this task a bit easier. But keep in mind that this blows the assembly size up and the initial XAP loading time will increase.
// Load an image from the calling Assembly's resources only by passing the relative path
var writeableBmp = new WriteableBitmap(0, 0).FromResource("example.png");

Uri for bitmap in subfolder (c# wpf)

I have a wpf app where I'm using an image. To reference the image I use:
Uri uri = new Uri("pack://application:,,,/assemblyName;Component/myIcon.png");
BitmapImage(uri)
If I add the png directly under the csproj file (with its properties BuildAction=Resource) then it works fine.
But I want to move it to a subfolder under the csproj. Another SO question asked about bitmaps\uri's (857732) and an answer linked to this msdn. So I tried :
Uri uri = new Uri("pack://application:,,,/assemblyName;Component/Icons/myIcon.png");
But that did not work.
Any ideas?

If the image is in your solution (i.e., you are not referencing the image from another assembly), you should be able to use this syntax:
Uri uri = new Uri("pack://application:,,,/Icons/myIcon.png", UriKind.Absolute);
Or, you can use a relative Uri as follows:
Uri uri = new Uri("/Icons/myIcon.png", UriKind.Relative);