Boolean CommandParameter in XAML

Matěj Zábský picture Matěj Zábský · Feb 14, 2011 · Viewed 53.2k times · Source

I have this code (which works just right):

<KeyBinding Key="Enter" Command="{Binding ReturnResultCommand}">
    <KeyBinding.CommandParameter>
        <s:Boolean>
            True
        </s:Boolean>
    </KeyBinding.CommandParameter>
</KeyBinding>

Where "s" is of course the System namespace.

But this command is called quite a few times and it really inflates otherwise rather simple XAML code. Is this really the shortest notation of boolean command parameter in XAML (other than splitting the command into several commands)?

Answer

H.B. picture H.B. · Feb 14, 2011

This might be a bit of a hack but you can derive from the KeyBinding class:

public class BoolKeyBinding : KeyBinding
{
    public bool Parameter
    {
        get { return (bool)CommandParameter; }
        set { CommandParameter = value; }
    }
}

Usage:

<local:BoolKeyBinding ... Parameter="True"/>

And another not so weird solution:

xmlns:s="clr-namespace:System;assembly=mscorlib"
<Application.Resources>
    <!-- ... -->
    <s:Boolean x:Key="True">True</s:Boolean>
    <s:Boolean x:Key="False">False</s:Boolean>
</Application.Resources>

Usage:

<KeyBinding ... CommandParameter="{StaticResource True}"/>