I think you forget to check the file type of all the files in your ''MyPictures' folder.
There might be some un-image files such as: Desktop.ini, Sample Pictures.lnk, Thumbs.db
Before you create instance of MyImage, you should make sure you put in an real image.
Below is a simple checking solution based on the filename, hope it helps.
For example:
public class MainContent
{
private List<MyImage> _AllImage;
public List<MyImage> AllImages
{
get
{
if (_AllImage == null)
{
_AllImage = new List<MyImage>();
foreach (string filename in System.IO.Directory.GetFiles(Environment.GetFolderPath(Environment.SpecialFolder.MyPictures)))
{
try
{
if (IsImage(filename))
{
MyImage mi = new MyImage(filename);
if (mi != null)
{
_AllImage.Add(new MyImage(filename));
}
}
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
}
}
return _AllImage;
}
}
public static string GetFileExt(string name)
{
return name.Substring(name.LastIndexOf(".") + 1);
}
public static bool IsImage( string name )
{
string ext = GetFileExt(name);
switch (ext.ToLower())
{
case "jpg":
case "jpeg":
return true;
case "bmp":
return true;
case "png":
return true;
case "gif":
return true;
//...... add more
default:
return false;
}
}
}
public class MyImage
{
public MyImage( string filename )
{
try
{
//Check the file is JPG,BMP...
_image = new BitmapImage();
_image.BeginInit();
_image.UriSource = new Uri(filename);
_image.EndInit();
_name = filename;
}
catch
{
}
}
public override string ToString()
{
return _name;
}
private BitmapImage _image;
public BitmapImage Image { get { return _image; } }
private string _name;
public string Name { get { return _name; } }
}
