wpf xaml calling a method on the current object - wpf

Question

Im attempting to bind to the output of a method. Now I've seen examples of this using ObjectDataProvider However the problem with this is ObjectDataProvider creates a new instance of the object to call the method. Where I need the method called on the current object instance. I'm currently trying to get a converter to work.
Setup:
Class Entity
{
private Dictionary<String, Object> properties;
public object getProperty(string property)
{
//error checking and what not performed here
return this.properties[property];
}
}
My attempt at the XAML
<local:PropertyConverter x:Key="myPropertyConverter"/>
<TextBlock Name="textBox2">
<TextBlock.Text>
<MultiBinding Converter="{StaticResource myPropertyConverter}"
ConverterParameter="Image" >
<Binding Path="RelativeSource.Self" /> <!--this doesnt work-->
</MultiBinding>
</TextBlock.Text>
</TextBlock>
my code behind
public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
{
string param = (string)parameter;
var methodInfo = values[0].GetType().GetMethod("getProperty", new Type[0]);
if (methodInfo == null)
return null;
return methodInfo.Invoke(values[0], new string[] { param });
}
public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
{
throw new NotSupportedException("PropertyConverter can only be used for one way conversion.");
}
My problem is that I cant seem to pass the current Entity into the converter. So When i try to use reflection to get the getProperty method I have nothing to operate on
thanks, steph

Answer 1

Wrap the call to the method inside a get property and add this get property to whatever class that is your current DataContext.
Edit: Answering your updated question.
If you only pass one parameter to the valueconverter you don't need a multivalueconverter, just use a regular valueconverter (implementing IValueConverter). Also, why not cast the object in the valueconverter to a Distionary and use it directly instead of using reflection.
To pass current datacontext as a binding do this: <Binding . />. I'm guessing the datacontext of the textblock is entity.
Still, all this is not necessary if all you want to do is run some code before accessing a dictionary item. Just use an index property instead, you can databind to it directly:
public class Entity
{
private Dictionary<String, Object> properties;
public object this[string property]
{
get
{
//error checking and what not performed here
return properties[property];
}
}
}
<TextBlock Text="{Binding Path=[Image]}" />