What happened to Control.InvokeRequired in WPF?

Question

I am writing a small WPF app which spawns some number of threads to stress test a page of a website. I would like to output some information in the textbox of the wpf form of state of the thread I am manually starting from the main WPF thread. I was kind of expecting the WPF to have the same capabilities as far as synchronizing my threads back to the GUI thread through:

  if(this.InvokeRequired)        this.Invoke(ProcessState); 

However there is nothing of the sorts in the WPF... what are the options to do the output from a non-gui thread in WPF?

Edit: The issue now appears to be in the fact that I am not able to check for the method CheckAccess() of the Dispatcher object of my control. I am running the 3.5 version of .net and VS 2008 SP1.

Here is the full metadata of my Dispatcher Class (F12 on it):

  using MS.Internal.WindowsBase;   using System;   using System.ComponentModel;   using System.Security;   using System.Threading;    namespace System.Windows.Threading   {      // Summary: //     Provides services for managing the queue of work items for a thread. public sealed class Dispatcher {     // Summary:     //     Gets the System.Windows.Threading.Dispatcher for the thread currently executing     //     and creates a new System.Windows.Threading.Dispatcher if one is not already     //     associated with the thread.     //     // Returns:     //     The dispatcher associated with the current thread.     public static Dispatcher CurrentDispatcher { get; }     //     // Summary:     //     Determines whether the System.Windows.Threading.Dispatcher has finished shutting     //     down.     //     // Returns:     //     true if the dispatcher has finished shutting down; otherwise, false.     public bool HasShutdownFinished { get; }     //     // Summary:     //     Determines whether the System.Windows.Threading.Dispatcher is shutting down.     //     // Returns:     //     true if the System.Windows.Threading.Dispatcher has started shutting down;     //     otherwise, false.     public bool HasShutdownStarted { get; }     //     // Summary:     //     Gets the collection of hooks that provide additional event information about     //     the System.Windows.Threading.Dispatcher.     //     // Returns:     //     The hooks associated with this System.Windows.Threading.Dispatcher.     [EditorBrowsable(EditorBrowsableState.Advanced)]     public DispatcherHooks Hooks { get; }     //     // Summary:     //     Gets the thread this System.Windows.Threading.Dispatcher is associated with.     //     // Returns:     //     The thread.     public Thread Thread { get; }      // Summary:     //     Occurs when the System.Windows.Threading.Dispatcher finishes shutting down.     public event EventHandler ShutdownFinished;     //     // Summary:     //     Occurs when the System.Windows.Threading.Dispatcher begins to shut down.     public event EventHandler ShutdownStarted;     //     // Summary:     //     Occurs when a thread exception is thrown and uncaught during execution of     //     a delegate by way of Overload:System.Windows.Threading.Dispatcher.Invoke     //     or Overload:System.Windows.Threading.Dispatcher.BeginInvoke.     public event DispatcherUnhandledExceptionEventHandler UnhandledException;     //     // Summary:     //     Occurs when a thread exception is thrown and uncaught during execution of     //     a delegate by way of Overload:System.Windows.Threading.Dispatcher.Invoke     //     or Overload:System.Windows.Threading.Dispatcher.BeginInvoke when in the filter     //     stage.     public event DispatcherUnhandledExceptionFilterEventHandler UnhandledExceptionFilter;      public DispatcherOperation BeginInvoke(Delegate method, params object[] args);     //     // Summary:     //     Executes the specified delegate asynchronously at the specified priority     //     on the thread the System.Windows.Threading.Dispatcher is associated with.     //     // Parameters:     //   priority:     //     The priority, relative to the other pending operations in the System.Windows.Threading.Dispatcher     //     event queue, the specified method is invoked.     //     //   method:     //     The delegate to a method that takes no arguments, which is pushed onto the     //     System.Windows.Threading.Dispatcher event queue.     //     // Returns:     //     An object, which is returned immediately after Overload:System.Windows.Threading.Dispatcher.BeginInvoke     //     is called, that can be used to interact with the delegate as it is pending     //     execution in the event queue.     //     // Exceptions:     //   System.ArgumentNullException:     //     method is null.     //     //   System.ComponentModel.InvalidEnumArgumentException:     //     priority is not a valid System.Windows.Threading.DispatcherPriority.     [EditorBrowsable(EditorBrowsableState.Never)]     [Browsable(false)]     public DispatcherOperation BeginInvoke(DispatcherPriority priority, Delegate method);     public DispatcherOperation BeginInvoke(Delegate method, DispatcherPriority priority, params object[] args);     //     // Summary:     //     Executes the specified delegate asynchronously at the specified priority     //     and with the specified argument on the thread the System.Windows.Threading.Dispatcher     //     is associated with.     //     // Parameters:     //   priority:     //     The priority, relative to the other pending operations in the System.Windows.Threading.Dispatcher     //     event queue, the specified method is invoked.     //     //   method:     //     A delegate to a method that takes one argument, which is pushed onto the     //     System.Windows.Threading.Dispatcher event queue.     //     //   arg:     //     The object to pass as an argument to the specified method.     //     // Returns:     //     An object, which is returned immediately after Overload:System.Windows.Threading.Dispatcher.BeginInvoke     //     is called, that can be used to interact with the delegate as it is pending     //     execution in the event queue.     //     // Exceptions:     //   System.ArgumentNullException:     //     method is null.     //     //   System.ComponentModel.InvalidEnumArgumentException:     //     priority is not a valid System.Windows.Threading.DispatcherPriority.     [EditorBrowsable(EditorBrowsableState.Never)]     [Browsable(false)]     public DispatcherOperation BeginInvoke(DispatcherPriority priority, Delegate method, object arg);     //     // Summary:     //     Executes the specified delegate asynchronously at the specified priority     //     and with the specified array of arguments on the thread the System.Windows.Threading.Dispatcher     //     is associated with.     //     // Parameters:     //   priority:     //     The priority, relative to the other pending operations in the System.Windows.Threading.Dispatcher     //     event queue, the specified method is invoked.     //     //   method:     //     A delegate to a method that takes multiple arguments, which is pushed onto     //     the System.Windows.Threading.Dispatcher event queue.     //     //   arg:     //     The object to pass as an argument to the specified method.     //     //   args:     //     An array of objects to pass as arguments to the specified method.     //     // Returns:     //     An object, which is returned immediately after Overload:System.Windows.Threading.Dispatcher.BeginInvoke     //     is called, that can be used to interact with the delegate as it is pending     //     execution in the System.Windows.Threading.Dispatcher queue.     //     // Exceptions:     //   System.ArgumentNullException:     //     method is null.     //     //   System.ComponentModel.InvalidEnumArgumentException:     //     System.Windows.Threading.DispatcherPriority is not a valid priority.     [Browsable(false)]     [EditorBrowsable(EditorBrowsableState.Never)]     public DispatcherOperation BeginInvoke(DispatcherPriority priority, Delegate method, object arg, params object[] args);     //     // Summary:     //     Initiates shutdown of the System.Windows.Threading.Dispatcher asynchronously.     //     // Parameters:     //   priority:     //     The priority at which to begin shutting down the dispatcher.     [SecurityCritical]     public void BeginInvokeShutdown(DispatcherPriority priority);     //     // Summary:     //     Determines whether the calling thread is the thread associated with this     //     System.Windows.Threading.Dispatcher.     //     // Returns:     //     true if the calling thread is the thread associated with this System.Windows.Threading.Dispatcher;     //     otherwise, false.     [EditorBrowsable(EditorBrowsableState.Never)]     public bool CheckAccess();     //     // Summary:     //     Disables processing of the System.Windows.Threading.Dispatcher queue.     //     // Returns:     //     A structure used to re-enable dispatcher processing.     public DispatcherProcessingDisabled DisableProcessing();     //     // Summary:     //     Requests that all frames exit, including nested frames.     [SecurityCritical]     public static void ExitAllFrames();     //     // Summary:     //     Gets the System.Windows.Threading.Dispatcher for the specified thread.     //     // Parameters:     //   thread:     //     The thread to obtain the System.Windows.Threading.Dispatcher from.     //     // Returns:     //     The dispatcher for thread.     public static Dispatcher FromThread(Thread thread);     public object Invoke(Delegate method, params object[] args);     //     // Summary:     //     Executes the specified delegate synchronously at the specified priority on     //     the thread on which the System.Windows.Threading.Dispatcher is associated     //     with.     //     // Parameters:     //   priority:     //     The priority, relative to the other pending operations in the System.Windows.Threading.Dispatcher     //     event queue, the specified method is invoked.     //     //   method:     //     A delegate to a method that takes no arguments, which is pushed onto the     //     System.Windows.Threading.Dispatcher event queue.     //     // Returns:     //     The return value from the delegate being invoked or null if the delegate     //     has no return value.     //     // Exceptions:     //   System.ArgumentException:     //     priority is equal to System.Windows.Threading.DispatcherPriority.Inactive.     //     //   System.ComponentModel.InvalidEnumArgumentException:     //     priority is not a valid priority.     //     //   System.ArgumentNullException:     //     method is null.     [Browsable(false)]     [EditorBrowsable(EditorBrowsableState.Never)]     public object Invoke(DispatcherPriority priority, Delegate method);     public object Invoke(Delegate method, DispatcherPriority priority, params object[] args);     public object Invoke(Delegate method, TimeSpan timeout, params object[] args);     //     // Summary:     //     Executes the specified delegate at the specified priority with the specified     //     argument synchronously on the thread the System.Windows.Threading.Dispatcher     //     is associated with.     //     // Parameters:     //   priority:     //     The priority, relative to the other pending operations in the System.Windows.Threading.Dispatcher     //     event queue, the specified method is invoked.     //     //   method:     //     A delegate to a method that takes one argument, which is pushed onto the     //     System.Windows.Threading.Dispatcher event queue.     //     //   arg:     //     An object to pass as an argument to the given method.     //     // Returns:     //     The return value from the delegate being invoked or null if the delegate     //     has no return value.     //     // Exceptions:     //   System.ArgumentException:     //     priority is equal to System.Windows.Threading.DispatcherPriority.Inactive.     //     //   System.ComponentModel.InvalidEnumArgumentException:     //     priority is not a valid priority.     //     //   System.ArgumentNullException:     //     method is null.     [EditorBrowsable(EditorBrowsableState.Never)]     [Browsable(false)]     public object Invoke(DispatcherPriority priority, Delegate method, object arg);     //     // Summary:     //     Executes the specified delegate synchronously at the specified priority and     //     with the specified time-out value on the thread the System.Windows.Threading.Dispatcher     //     was created.     //     // Parameters:     //   priority:     //     The priority, relative to the other pending operations in the System.Windows.Threading.Dispatcher     //     event queue, the specified method is invoked.     //     //   timeout:     //     The maximum time to wait for the operation to finish.     //     //   method:     //     The delegate to a method that takes no arguments, which is pushed onto the     //     System.Windows.Threading.Dispatcher event queue.     //     // Returns:     //     The return value from the delegate being invoked or null if the delegate     //     has no return value.     [Browsable(false)]     [EditorBrowsable(EditorBrowsableState.Never)]     public object Invoke(DispatcherPriority priority, TimeSpan timeout, Delegate method);     public object Invoke(Delegate method, TimeSpan timeout, DispatcherPriority priority, params object[] args);     //     // Summary:     //     Executes the specified delegate at the specified priority with the specified     //     arguments synchronously on the thread the System.Windows.Threading.Dispatcher     //     is associated with.     //     // Parameters:     //   priority:     //     The priority, relative to the other pending operations in the System.Windows.Threading.Dispatcher     //     event queue, the specified method is invoked.     //     //   method:     //     A delegate to a method that takes multiple arguments, which is pushed onto     //     the System.Windows.Threading.Dispatcher event queue.     //     //   arg:     //     An object to pass as an argument to the given method.     //     //   args:     //     An array of objects to pass as arguments to the given method.     //     // Returns:     //     The return value from the delegate being invoked or null if the delegate     //     has no return value.     //     // Exceptions:     //   System.ArgumentException:     //     priority is equal to System.Windows.Threading.DispatcherPriority.Inactive.     //     //   System.ComponentModel.InvalidEnumArgumentException:     //     priority is not a valid priority.     //     //   System.ArgumentNullException:     //     method is null.     [EditorBrowsable(EditorBrowsableState.Never)]     [Browsable(false)]     public object Invoke(DispatcherPriority priority, Delegate method, object arg, params object[] args);     //     // Summary:     //     Executes the specified delegate at the specified priority with the specified     //     argument synchronously on the thread the System.Windows.Threading.Dispatcher     //     is associated with.     //     // Parameters:     //   priority:     //     The priority, relative to the other pending operations in the System.Windows.Threading.Dispatcher     //     event queue, the specified method is invoked.     //     //   timeout:     //     The maximum time to wait for the operation to finish.     //     //   method:     //     A delegate to a method that takes multiple arguments, which is pushed onto     //     the System.Windows.Threading.Dispatcher event queue.     //     //   arg:     //     An object to pass as an argument to the given method. This can be null if     //     no arguments are needed.     //     // Returns:     //     The return value from the delegate being invoked or null if the delegate     //     has no return value.     //     // Exceptions:     //   System.ArgumentException:     //     priority is equal to System.Windows.Threading.DispatcherPriority.Inactive.     //     //   System.ComponentModel.InvalidEnumArgumentException:     //     priority is not a valid priority.     //     //   System.ArgumentNullException:     //     method is null.     [EditorBrowsable(EditorBrowsableState.Never)]     [Browsable(false)]     public object Invoke(DispatcherPriority priority, TimeSpan timeout, Delegate method, object arg);     //     // Summary:     //     Executes the specified delegate at the specified priority with the specified     //     arguments synchronously on the thread the System.Windows.Threading.Dispatcher     //     is associated with.     //     // Parameters:     //   priority:     //     The priority, relative to the other pending operations in the System.Windows.Threading.Dispatcher     //     event queue, the specified method is invoked.     //     //   timeout:     //     The maximum time to wait for the operation to finish.     //     //   method:     //     A delegate to a method that takes multiple arguments, which is pushed onto     //     the System.Windows.Threading.Dispatcher event queue.     //     //   arg:     //     An object to pass as an argument to the specified method.     //     //   args:     //     An array of objects to pass as arguments to the specified method.     //     // Returns:     //     The return value from the delegate being invoked or null if the delegate     //     has no return value.     //     // Exceptions:     //   System.ArgumentException:     //     priority is equal to System.Windows.Threading.DispatcherPriority.Inactive.     //     //   System.ComponentModel.InvalidEnumArgumentException:     //     priority is not a valid System.Windows.Threading.DispatcherPriority.     //     //   System.ArgumentNullException:     //     method is null.     [Browsable(false)]     [EditorBrowsable(EditorBrowsableState.Never)]     public object Invoke(DispatcherPriority priority, TimeSpan timeout, Delegate method, object arg, params object[] args);     //     // Summary:     //     Initiates the shutdown process of the System.Windows.Threading.Dispatcher     //     synchronously.     [SecurityCritical]     public void InvokeShutdown();     //     // Summary:     //     Enters an execute loop.     //     // Parameters:     //   frame:     //     The frame for the dispatcher to process.     //     // Exceptions:     //   System.ArgumentNullException:     //     frame is null.     //     //   System.InvalidOperationException:     //     System.Windows.Threading.Dispatcher.HasShutdownFinished is true -or- frame     //     is running on a different System.Windows.Threading.Dispatcher.  -or- Dispatcher     //     processing has been disabled.     [SecurityCritical]     public static void PushFrame(DispatcherFrame frame);     //     // Summary:     //     Pushes the main execution frame on the event queue of the System.Windows.Threading.Dispatcher.     [SecurityCritical]     public static void Run();     //     // Summary:     //     Determines whether the specified System.Windows.Threading.DispatcherPriority     //     is a valid priority.     //     // Parameters:     //   priority:     //     The priority to check.     //     //   parameterName:     //     A string that will be returned by the exception that occurs if the priority     //     is invalid.     //     // Exceptions:     //   System.ComponentModel.InvalidEnumArgumentException:     //     priority is not a valid System.Windows.Threading.DispatcherPriority.     public static void ValidatePriority(DispatcherPriority priority, string parameterName);     //     // Summary:     //     Determines whether the calling thread has access to this System.Windows.Threading.Dispatcher.     //     // Exceptions:     //   System.InvalidOperationException:     //     The calling thread does not have access to this System.Windows.Threading.Dispatcher.     [EditorBrowsable(EditorBrowsableState.Never)]     public void VerifyAccess(); } 

}

Answer 1

In WPF, this was moved out of the Control/UIElement hierarchy, and into the dispatcher.

The equivelent is Dispatcher.CheckAccess and Dispatcher.Invoke.

You should be able to do:

if (someControl.Dispatcher.CheckAccess())       UpdateUI(); else     someControl.Dispatcher.Invoke(new Action(UpdateUI)); 

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Your metadata includes:

// // Summary: //     Determines whether the calling thread is the thread associated with this //     System.Windows.Threading.Dispatcher. // // Returns: //     true if the calling thread is the thread associated with this System.Windows.Threading.Dispatcher; //     otherwise, false. [EditorBrowsable(EditorBrowsableState.Never)] public bool CheckAccess(); 

This is the method you want to use... It doesn't show up in Intellisense, but it is there, and it does work correctly.