WPF CommandParameter in Textbox

Question

Hi,

I am using MVVM pattern and i have a textbox in parent window and want to send some text to the popup window which will appear on Textchanged.

I tried using commandparameter but it is not working for me.

Please help..

Thanks Sharath

Answer 1

What have you tried? This code works for me:

<Window x:Class="WpfApplication1.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Window1" Height="300" Width="300">
    <Window.CommandBindings>
        <CommandBinding Command="Cut" Executed="CommandBinding_Executed" />
    </Window.CommandBindings>
    <StackPanel>
        <TextBox x:Name="textBox1" />
        <Button Command="Cut" 
                CommandParameter="{Binding Text,ElementName=textBox1}" 
                Content="Cut" />
    </StackPanel>
</Window>

With this event handler:

private void CommandBinding_Executed(object sender, ExecutedRoutedEventArgs e)
{
    MessageBox.Show(e.Parameter.ToString());
}

Answer 2

If i want the command to be executed if the user presses enter, i like to use this. Note the clever use of the IsDefault Binding :-)

<TextBox x:Name="inputBox"/>
<Button Command="{Binding CutCommand}" 
        CommandParameter="{Binding Text, ElementName=inputBox}" 
        Content="Cut" 
        IsDefault="{Binding IsFocused, ElementName=inputBox}" />

If you don't want the button to be visible, you can set its visibility to collapsed of course. I think it'll still execute the command if you hit enter.