C# 4 and .NET 4

Markup extensions ❘ 743
public override object ProvideValue(IServiceProvider serviceProvider)
{
IProvideValueTarget provideValue =
serviceProvider.GetService(typeof(IProvideValueTarget))
as IProvideValueTarget;
if (provideValue != null)
{
var host = provideValue.TargetObject as FrameworkElement;
var prop = provideValue.TargetProperty as DependencyProperty;
}
double result = 0;
switch (Operation)
{
case Operation.Add:
result = X + Y;
break;
case Operation.Subtract:
result = X - Y;
break;
case Operation.Multiply:
result = X * Y;
break;
case Operation.Divide:
result = X / Y;
break;
default:
throw new ArgumentException("invalid operation");
}
}
}
}
return result.ToString();
code snippet MarkupExtensionDemo/CalculatorExtension.cs
The markup extension can now be used with an attribute syntax in the first TextBlock to add the values 3
and 4, or with the element syntax with the second TextBlock.
Multiply
7
11
code snippet MarkupExtensionDemo/MainWindow.xaml
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