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Ignoring text / value changes due to data binding

How to ignore changes in a control when data binding occurs? I tried connecting various events, such as gotfocus, textchanged and leavefocus, but if the control already has focus and the user "cancels" their changes, when I reload recording and data binding, the textchanged command thinks that the user still made the changes. since the focus is on this control. The call stack is empty. Are there any global data binding events, such as the beginning of a data binding and the completion of a data binding? I see where I run OnProperyChanged, but no data binding occurs inside this call. It appears to be queuing up and working elsewhere.

At some point, I was going to intercept property change events in our view model, but this means that I will not detect and cannot visually display the form that has been changed until the user leaves the control. I know, I know, I can change all my bindings so that the binding happens immediately every time the symbol changes, but then this is a mess with some cases of verification, since the user did not finish entering their value.

I would really like some kind of event, such as TextChangedByUser, which could lead to the user using the key, clipboard, clipboard for the mouse, anything caused by the user.

I just can't figure out how to distinguish between user changes and data binding changes.

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3

- , TextChangedByUser, , , , .

, .

Text.TextChanged ,
Binding.SourceUpdated .

: DP , Binding.SourceUpdated .

RoutedEvent. NotifyOnSourceUpdated = true. UpdateSourceTrigger , .

</" > xaml :

<Grid x:Name="LayoutRoot" Binding.SourceUpdated="LayoutRoot_SourceUpdated">
    ...
    <TextBox>
        <TextBox.Text>
            <Binding NotifyOnSourceUpdated="True" Path="path" UpdateSourceTrigger="PropertyChanged" >
            </Binding>
        </TextBox.Text>
</Grid>

:

private void LayoutRoot_SourceUpdated(object sender, DataTransferEventArgs e)
{
    // called every time s.th. changed by user
}

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, - ?
"" TextBox DataContext , TextBox.Text - target.
[ ] http://msdn.microsoft.com/en-us/library/ms752347.aspx
TextBox.Text , TextBox.Text. , , TextBox.Text (, TextChanged) . : Text.TextChanged !!! : DP .

, , "TextBox.Text" ( ). , UpdateSourceTrigger. SourceUpdated.

, . - Desktop-, , .

+6

,

{Binding Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}

EDIT: , , ... : (

0

You can use the UIElement.TextInput event to detect user input.

Note that the event is probably already being processed by the input control itself, so you might need the UIElement.PreviewTextInput event .

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