Question

Is it possible to use value converters without having to define them beforehand as resources?

Right now I have

<Window.Resources>
    <local:TrivialFormatter x:Key="trivialFormatter" />
</Window.Resources>

and

<Button Width="{Binding Width, 
               ElementName=textBox1, 
               UpdateSourceTrigger=PropertyChanged, 
               Converter={StaticResource trivialFormatter}}">

Wouldn’t it be possible that instead of having to declare the trivialFormatter resource in Window.Resources, I could directly refer it from the Button’s width binding? Something like

Converter = {local:TrivialFormatter}

Thanks

Answer 1

In the case of singleton-type IValueConverters (e.g. they don’t need any state from the current binding instance) I use static converters, i.e.:

Converter={x:Static SomeNamespace:SomeConverter.Instance}

There’s also a great post by Dr. WPF on using a markup extension to make it cleaner inline here.