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POWPF Can't Databind to an Interface?
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  1. POWPF Can't Databind to an Interface?
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    copied!<p>I'm trying to bind controls in a WPF form to an interface and I get a runtime error that it can't find the interface's properties.</p> <p>Here's the class I'm using as a datasource:</p> <pre><code>public interface IPerson { string UserId { get; set; } string UserName { get; set; } string Email { get; set; } } public class Person : EntityBase, IPerson { public virtual string UserId { get; set; } public string UserName { get; set; } public virtual string Email { get; set; } } </code></pre> <p>Here's the XAML (an excerpt):</p> <pre><code>&lt;TextBox Name="userIdTextBox" Text="{Binding UserId}" /&gt; &lt;TextBox Name="userNameTextBox" Text="{Binding UserName}" /&gt; &lt;TextBox Name="emailTextBox" Text="{Binding Email}" /&gt; </code></pre> <p>Here's the code behind (again, an excerpt):</p> <pre><code>var person = PolicyInjection.Wrap&lt;IPerson&gt;(new Person()); person.UserId = "jdoe"; person.UserName = "John Doe"; person.Email = "jdoe@live.com"; this.DataContext = person; </code></pre> <p>Note that the class I'm using as the data source needs to be an entity because I'm using Policy Injection through the entlib's Policy Injection Application Block.</p> <p>I'm getting this error at runtime:</p> <pre><code>System.Windows.Data Error: 16 : Cannot get 'Email' value (type 'String') from '' (type 'Person'). BindingExpression:Path=Email; DataItem='Person' (HashCode=22322349); target element is 'TextBox' (Name='emailTextBox'); target property is 'Text' (type 'String') TargetException:'System.Reflection.TargetException: Object does not match target type. at System.Reflection.RuntimeMethodInfo.CheckConsistency(Object target) at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture, Boolean skipVisibilityChecks) at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture) at System.Reflection.RuntimePropertyInfo.GetValue(Object obj, BindingFlags invokeAttr, Binder binder, Object[] index, CultureInfo culture) at System.Reflection.RuntimePropertyInfo.GetValue(Object obj, Object[] index) at MS.Internal.Data.PropertyPathWorker.GetValue(Object item, Int32 level) at MS.Internal.Data.PropertyPathWorker.RawValue(Int32 k)' </code></pre>
 

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