WPF TexBox TwoWay Binding Problem when ValidationRules used

Posted by ignis on Stack Overflow See other posts from Stack Overflow or by ignis
Published on 2010-04-14T06:37:44Z Indexed on 2010/04/14 6:43 UTC
Read the original article Hit count: 386

Filed under:

wpf

|

xaml

|

databinding

I seem to have a problem with TwoWay DataBinding - my application has a window with a bunch of textboxes that allow to edit values of the properties they are bound to. Everything works well except for textboxes that also have a validation rule defined, in which case no text is displayed in the textbox when the window opens (binding back-to-source still works fine for those). If I remove Validation rule, everything's back to normal. I searched for an answer to this for a few hours now, but somehow did not even find anyone else complaining of the same issue. I am completely new to WPF, and I am sure it is just a silly mistake I have somewhere in my code... I will greatly appreciate any feedback...

<TextBox Margin="40,2,20,0" Grid.Column="0" Grid.Row="1" Background="#99FFFFFF" >
        <Binding Path="LastName" Mode="TwoWay" ValidatesOnDataErrors="true" UpdateSourceTrigger="LostFocus" >
                    <Binding.ValidationRules>
                        <validation:StringNameValidationRule />
                    </Binding.ValidationRules>
        </Binding>
</TextBox>

© Stack Overflow or respective owner

Related posts about wpf

C#/WPF - RoutedEvent in WPF class that isn't a UIElement

as seen on Stack Overflow - Search for 'Stack Overflow'
I have a class that needs to notify that something significant has occured. The class is in a WPF-project, even though this specific class, is lookless (and doesn't inherit from UIElement, neither directly or indirectly). Normally, I just register a RoutedEvent to get this functionality but as this… >>> More
How to pass value from wpf form to wpf user control

as seen on Stack Overflow - Search for 'Stack Overflow'
Hai am having a WPF user control in my WPF Form, when i click my button in my form , i just want to pass some value to the textbox which is in the usercontrol, tell me how to do this. >>> More
WPF opening up exe program within WPF window

as seen on Stack Overflow - Search for 'Stack Overflow'
Not sure if this is possible but is there a way to open up another program like notepad within the container of a WPF window? similiar to that of being able to open a web page using the webbrowser control? Basically I would like to open notepad or other exe but keep it constrained within the WPF… >>> More
Silverlight Commands Hacks: Passing EventArgs as CommandParameter to DelegateCommand triggered by Ev

as seen on ASP.net Weblogs - Search for 'ASP.net Weblogs'
Today I've tried to find a way how to pass EventArgs as CommandParameter to DelegateCommand triggered by EventTrigger. By reverse engineering of default InvokeCommandAction I find that blend team just ignores event args.To resolve this issue I have created my own action for triggering delegate commands… >>> More
Building applications with WPF, MVVM and Prism(aka CAG)

as seen on ASP.net Weblogs - Search for 'ASP.net Weblogs'
In this article I am going to walk through an application using WPF and Prism (aka composite application guidance, CAG) which simulates engaging a taxi (cab). The rules are simple, the app would have3 screens A login screen to authenticate the user An information screen. A screen… >>> More

Related posts about xaml

Getting Started Building Windows 8 Store Apps with XAML/C#

as seen on ASP.net Weblogs - Search for 'ASP.net Weblogs'
Technology is fun isn’t it? As soon as you think you’ve figured out where things are heading a new technology comes onto the scene, changes things up, and offers new opportunities. One of the new technologies I’ve been spending quite a bit of time with lately is Windows 8 store applications. I posted… >>> More
XAML and WPF - Passing Variables to XAML Windows

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I'm pretty new to WPF and i'm trying to load a XAML window and pass a variable to this XAML in its constructor or so, because i need it to load some items from this passed variable. Could anyone point me to the direction of how to go about this please? How does one start up a XAML window and… >>> More
Silverlight insert XAML inside other XAML

as seen on Stack Overflow - Search for 'Stack Overflow'
I am using WPF and Silverlight BookControls by Mitsu http://www.codeplex.com/wpfbookcontrol The WPF example alows that every page in the book to be a XAML file, but the Silverlight example dont. Is there a way load a XAML in every book page in the Silverlight example ? >>> More
WPF: Xaml, create an observable collection<object> in xaml in Dot Net 4.0

as seen on Stack Overflow - Search for 'Stack Overflow'
the web site says you can in dot net 4.0 I cant seem to do it though, what assesmbly references and xmlns' do i need the following does not work xmlns:coll="clr-namespace:System.Collections.ObjectModel;assembly=mscorlib" <coll:ObservableCollection x:TypeArguments="x:Object"> <MenuItem… >>> More
WPF: Xaml, create an observable collection<object> in xaml in .NET 4.0

as seen on Stack Overflow - Search for 'Stack Overflow'
the web site says you can in .NET 4.0 I cant seem to do it though, what assesmbly references and xmlns' do i need the following does not work xmlns:coll="clr-namespace:System.Collections.ObjectModel;assembly=mscorlib" <coll:ObservableCollection x:TypeArguments="x:Object"> <MenuItem… >>> More