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    <p>Straightaway porting is not possible but can we "simulate" this using <code>MultiBinding</code></p> <p>Mind you that this is very tightly coupled solution and may not perform well if many of such bindings are used on a page...</p> <p>Two <strong>must haves</strong> ...</p> <ol> <li>It accepts the delay in milliseconds in a single item <code>ArrayList</code> as a converter parameter. </li> <li>Every such delayed binding must carry its own instance of converter parameter.</li> </ol> <p>The Test XAML is as below...</p> <pre><code> &lt;TextBlock xmlns:Collections="clr-namespace:System.Collections;assembly=mscorlib" xmlns:System="clr-namespace:System;assembly=mscorlib" &gt; &lt;TextBlock.Resources&gt; &lt;local:DelayHelper x:Key="DelayHelper"/&gt; &lt;Collections:ArrayList x:Key="MultiConverterParameter"&gt; &lt;System:Int32&gt;2000&lt;/System:Int32&gt; &lt;/Collections:ArrayList&gt; &lt;/TextBlock.Resources&gt; &lt;TextBlock.Text&gt; &lt;MultiBinding UpdateSourceTrigger="LostFocus" Converter="{StaticResource DelayHelper}" ConverterParameter="{StaticResource MultiConverterParameter}"&gt; &lt;Binding Path="Text" ElementName="MyTextBox" Mode="OneWay" /&gt; &lt;Binding RelativeSource="{RelativeSource Self}"/&gt; &lt;Binding BindsDirectlyToSource="True" Source="{x:Static TextBlock.TextProperty}"/&gt; &lt;/MultiBinding&gt; &lt;/TextBlock.Text&gt; &lt;/TextBlock&gt; &lt;TextBox x:Name="MyTextBox" Text="Test..."/&gt; </code></pre> <p>In this example a <code>TextBlock</code> renders of what is typed in <code>TextBox</code> below after a 2 seconds delay. The <code>TextBox.Text</code> is primary source of data.</p> <p><code>DelayHelper</code> is multi converter that works as shown below...</p> <pre><code>public class DelayHelper : IMultiValueConverter { #region IMultiValueConverter Members public object Convert( object[] values, Type targetType, object parameter, System.Globalization.CultureInfo culture) { var sourceElement = values[1] as FrameworkElement; var dp = values[2] as DependencyProperty; var paramArray = parameter as ArrayList; var existingValue = paramArray != null &amp;&amp; paramArray.Count == 2 ? paramArray[1] : sourceElement.GetValue(dp); var newValue = values[0]; var bndExp = BindingOperations.GetMultiBindingExpression(sourceElement, dp); var temp = new DispatcherTimer() { IsEnabled = false }; var dspTimer = new DispatcherTimer( new TimeSpan(0,0,0,0, int.Parse(paramArray[0].ToString())), DispatcherPriority.Background, new EventHandler( delegate { if (bndExp != null &amp;&amp; existingValue != newValue) { var array = bndExp.ParentMultiBinding.ConverterParameter as ArrayList; var existingInterval = array[0]; array.Clear(); array.Add(existingInterval); array.Add(newValue); bndExp.UpdateTarget(); } temp.Stop(); }), sourceElement.Dispatcher); temp = dspTimer; dspTimer.Start(); return existingValue; } public object[] ConvertBack( object value, Type[] targetTypes, object parameter, System.Globalization.CultureInfo culture) { throw new NotImplementedException(); } #endregion } </code></pre> <p>So this code makes use of the facts that </p> <ol> <li>MultiBinding can accept the target UI element (<code>TextBlock</code>) and its dependency property (<code>TextBlock.TextProperty</code>) that itself is multi-bound.</li> <li>Once bound the multi binding cannot alter its properties including the <code>ConveterParameter</code>. But the converter parameter itself can be a reference object that maintains its reference throughout the binding is active e.g. <code>ArrayList</code>.</li> <li>The <code>DispatcherTimer</code> has to stop after its first <code>Tick</code>. Hence we use of the <code>temp</code> variable is very essential.</li> <li>The updates make 2 converter passes for each source text update. There is no escpae from this behavior. This may cause slowness is many delayed bindings are used.</li> <li><strong>Make sure you do not share the same converter parameter among multiple delayed bindings</strong> </li> </ol> <p>Let me know if this helps...</p>
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    1. PODelay property on Binding from .Net 4.5 in .Net 4.0
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    1. USWPF-it
    1. USWPF-it
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    1. COCan you elaborate ?
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    2. COUnfortunately as far as I know converter is evaluated in UI thread and IsAsync is not affecting it.
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    3. CO@baalazamon, please see my edited reply again. :-)
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