XAML绑定

public class Follower { 
　　private List<Skill> skillList; 
　　Dictionary<string, Item> itemList = new Dictionary<string, Item>(); 

　　public List<Skill> SkillList { get { return this.skillList; } } 
　　public Dictionary<string, Item> ItemList { get { return this.itemList; } }

如上是追随者的结构。如下绑定主手装备到XAML上

<Border BorderThickness="1" Height="96" Canvas.Left="149" Canvas.Top="164" Width="50" BorderBrush="{Binding ItemList[mainhand].BorderBrush}">
            <Border.Background>
                <ImageBrush ImageSource="{Binding ItemList[mainhand].BorderBackGround}"/>
            </Border.Background>
            <Image Source="{Binding ItemList[mainhand].ItemImage}" Height="96" Canvas.Left="596" Canvas.Top="120" Width="50" Margin="0,0,0,0" />
        </Border>

 注意的是代码中实际是ItemList["mainhand"].BorderBrush，而在XAML中，两个双引号是不能写的。

如果要绑定技能2到XAML上，如下，可以使用数字index。

<Border BorderThickness="1" Height="24" Canvas.Left="40" Canvas.Top="182" Width="24">
            <Border.Background>
                <ImageBrush ImageSource="{Binding SkillList[2].SkillImage}"/>
            </Border.Background>
        </Border>

 而如果要绑定collections的层级结构，则使用/即可。如下是msdn中path的解释

• Use the Path property to specify the source value you want to bind to:
  • In the simplest case, the Path property value is the name of the property of the source object to use for the binding, such as Path=PropertyName.
  • Subproperties of a property can be specified by a syntax similar to that used in C#. For instance, the clause Path=ShoppingCart.Order sets the binding to the subproperty Order of the object or property ShoppingCart.
  • To bind to an attached property, place parentheses around the attached property. For example, to bind to the attached property DockPanel.Dock, the syntax isPath=(DockPanel.Dock).
  • Indexers of a property can be specified within square brackets following the property name where the indexer is applied. For instance, the clause Path=ShoppingCart[0] sets the binding to the index that corresponds to how your property's internal indexing handles the literal string "0". Multiple indexers are also supported.
  • Indexers and subproperties can be mixed in a Path clause; for example, Path=ShoppingCart.ShippingInfo[MailingAddress,Street].
  • Inside indexers you can have multiple indexer parameters separated by commas (,). The type of each parameter can be specified with parentheses. For example, you can have Path="[(sys:Int32)42,(sys:Int32)24]", where sys is mapped to the System namespace.
  • When the source is a collection view, the current item can be specified with a slash (/). For example, the clause Path=/ sets the binding to the current item in the view.
  • When the source is a collection, this syntax specifies the current item of the default collection view.
  • Property names and slashes can be combined to traverse properties that are collections. For example, Path=/Offices/ManagerName specifies the current item of the source collection, which contains an Offices property that is also a collection. Its current item is an object that contains a ManagerName property. Optionally, a period (.) path can be used to bind to the current source. For example, Text="{Binding}" is equivalent to Text="{Binding Path=.}".

补充一下，WP8开发中，app bar的icon，要求很龌龊：透明、alpha、白色前景。

我在Mspaint中画不出来，不知道怎么搞透明背景。后来搞定的方式是，vs2012中打开sdk中带的icon，把原有的select/delete掉，然后画上我自己要求的文字。 

 代码如下，出现错误，不能operated在这个stream上

public static BitmapImage GetBitmapFromIsolatedFolderByName(string file)
        {
            BitmapImage image = new BitmapImage();
            
            var stream = localFolder.OpenFile(cachePath+"\\"+file, System.IO.FileMode.Open);
            image.SetSource(stream);
            stream.Close();

            return image;

        }

 重点在于红色那一行，如果不close，那么第二次就会发生这个exception。令人发指的是，发生exception的时候，callstack都是reflection的东西，看不到真正的root cause。