Arithmetic operations in Xaml
One of the common hurdles (if you may call that) that I face while writing some xaml is performing simple arithmetic operations while binding. hmm... i am sure many have faced the same... The solution is writing an IValueConverter and you are set... For simple math like [ActualHeight+10] we can readily use the ArithmeticConverter code. This will allow operations like
1 <Window.Resources>
2 <local:ArithmeticConverter x:Key="arithConverter" />
3 </Window.Resources>
4 <TextBlock Height="{Binding ElementName=tb1, Path=ActualHeight,
5 Converter={StaticResource AScript}, ConverterParameter=Int32.Parse(values[0])-100 }" />
The code however will not do multiple arithmetic operations. I really didnt need a converter which did more than that. However, Douglas has written a converter which does exactly that and extends it further to multibinding. Now using his converter we can perform operations like the below in Xaml.
1 <StackPanel.Resources>
2 <local:JScriptConverter x:Key="JScript" TrapExceptions="False" />
3 </StackPanel.Resources>
4 <TextBlock Height="{Binding ElementName=tb1, Path=ActualHeight,
5 Converter={StaticResource JScript},
6 ConverterParameter=Int32.Parse(values[0])/10 *100-110 }" Background="Red"/>
PS: both the converters are attached in a sample project.
