Public Overloads Sub ExecuteAsync( _
   ByVal printParameters As PrintParameters, _
   ByVal userToken As Object _
) 

public void ExecuteAsync( 
   PrintParameters printParameters,
   object userToken
)

<Grid x:Name="LayoutRoot" Background="White">
  <esri:Map Background="White" HorizontalAlignment="Left" Margin="12,261,0,0" 
            Name="MyMap" VerticalAlignment="Top" WrapAround="True" Height="300" Width="600"
             Extent="-10929488.234,4525208.388,-10906776.553,4535252.104">
    <esri:Map.Layers>
      <esri:LayerCollection>
      
        <!-- Add some layers to the Map Control. -->
        <esri:ArcGISTiledMapServiceLayer 
          Url="http://server.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer" />
        <esri:FeatureLayer Mode="OnDemand" DisableClientCaching="True" 
          Url="http://sampleserver3.arcgisonline.com/ArcGIS/rest/services/Petroleum/KSWells/MapServer/0" />
        
      </esri:LayerCollection>
    </esri:Map.Layers>
  </esri:Map>
  
  <!-- Url -->
  <sdk:Label Height="20" HorizontalAlignment="Left" Margin="8,100,0,0" Name="Label_Url" 
             VerticalAlignment="Top" Width="31" Content="Url:"/>
  <TextBox Height="23" HorizontalAlignment="Left" Margin="8,118,0,0" Name="TextBox_Url" 
           VerticalAlignment="Top" Width="605" FontSize="10" />
  
  <!-- Buttons to perform the work. -->
  <Button Content="ExecuteAsync" Height="39" Width="201" HorizontalAlignment="Left" Margin="12,147,0,0" 
          Name="Button_ExecuteAsync" VerticalAlignment="Top" Click="Button_ExecuteAsync_Click" IsEnabled="True"/>
  <Button Content="CancelAsync" Height="35" Width="201" HorizontalAlignment="Left" Margin="12,192,0,0" 
          Name="Button_CancelAsync" VerticalAlignment="Top" Click="Button_CancelAsync_Click" IsEnabled="False"/>
  
  <!-- Provide PrintTask information messages. -->
  <sdk:Label Height="19" HorizontalAlignment="Left" Margin="229,147,0,0" Name="Label_StatusInfo" 
             VerticalAlignment="Top" Width="120" Content="Status Information:"/>
  <ListBox Height="64" HorizontalAlignment="Left" Margin="229,163,0,0" Name="ListBox_StatusInformation" 
           VerticalAlignment="Top" Width="383" />
  
  <!-- Provide the instructions on how to use the sample code. -->
  <TextBlock Height="94" HorizontalAlignment="Left" Name="TextBlock1" VerticalAlignment="Top" Width="625" 
     TextWrapping="Wrap" Text="When the application loads, enter a correct Url to an ArcGIS Server PrintTask 
      based on a 'synchronous geoprocessing task'. Then click the 'ExecuteAsync' button to generate a
      .JPG image returned in an internet browser. Status informatonal messages will display to provide 
      information on the PrintTask operation. Experiment by clicking the 'ExecuteAsync' button in rapid 
      succession (ie. before the PrintTask has a chance to complete generating an image/.pdf file to better 
      understand how a 'synchronous geoprocesing task' works." />
    
</Grid>

// Create a Global (aka. Member) variable for the PrintTask object that will be used in other 
// parts of the application.
private ESRI.ArcGIS.Client.Printing.PrintTask _PrintTask;
            
public MainPage()
{
  InitializeComponent();
  
  // Provide a valid PrintTask.Url for a "synchronous geoprocessing task"
  TextBox_Url.Text = "http://localhost:6080/arcgis/rest/services/Utilities/PrintingTools/GPServer/Export20Web20Map%20Task";
  
  // Set the _PrintTask variable to a new instance of the PrintTask Class.
  _PrintTask = new ESRI.ArcGIS.Client.Printing.PrintTask();
  
  // Prevent the internet browser from using a cache for the PrintTask operations.
  _PrintTask.DisableClientCaching = true;
  
  // Set the PrintTask.Url from what is entered in the TextBox.
  _PrintTask.Url = TextBox_Url.Text;
  
  // Wire up an Event Handler for the PrintTask.ExecuteCompleted Event.
  _PrintTask.ExecuteCompleted += printTask_ExecuteCompleted;
}
            
private void Button_ExecuteAsync_Click(object sender, System.Windows.RoutedEventArgs e)
{
  // Define the settings for rendering the image/.pdf on the ArcGIS Server.
  
  // Define the ExportOptions.
  ESRI.ArcGIS.Client.Printing.ExportOptions myExportOptions = new ESRI.ArcGIS.Client.Printing.ExportOptions();
  myExportOptions.Dpi = 96; //96 DPI is typical Window OS setting.
  myExportOptions.OutputSize = new Size(MyMap.ActualWidth, MyMap.ActualHeight); // Use the dimensions of the Map
  
  // Define the PrintParameters.
  ESRI.ArcGIS.Client.Printing.PrintParameters myPrintParameters = new ESRI.ArcGIS.Client.Printing.PrintParameters(MyMap);
  myPrintParameters.ExportOptions = myExportOptions; // Use the ExportOptions defined earlier.
  myPrintParameters.LayoutTemplate = "MAP_ONLY"; // Look to the REST service to see what layout templates are supported.
  myPrintParameters.Format = "JPG"; // Look to the REST service to see what image formats are supported.
  
  // NOTE: 
  // If you try to submit more that one 'synchronous geoprocessing task' via PrintTask.ExecuteAsync at a time 
  // using the ExecuteAsync methadology you will get a Visual Studio (Runtime) error: 
  // NotSupportedException was unhandled by user code. "Task does not support concurrent  I/O operations. Cancel 
  // the pending request or wait for it to complete." 
  // In order to overcome this, use the PrintTask.IsBusy Property and take action accordingly.
  
  if (_PrintTask.IsBusy == true)
  {
    // There is an existing 'synchronous geoprocessing task' PrintTask running. 
    
    // Use a simple MessageBox to get user direction on whether to stay with the currently running 'synchronous 
    // geoprocessing task' PrintTask or cancel it and start another one.
    System.Windows.MessageBoxResult myMessage = MessageBox.Show("Click 'Cancel' to kill the prior print job and print this one OR click 'OK' to finish the prior " + "print job and wait to re-click the Print button.", "Action Required", MessageBoxButton.OKCancel);
    
    if (myMessage == MessageBoxResult.Cancel)
    {
      // The user has opted to cancel the currently runnning 'synchronous geoprocessing task' PrintTask. 
      
      // Kill the PrintTask.
      _PrintTask.CancelAsync();
      
      // Clear out the status informational messages. 
      ListBox_StatusInformation.Items.Clear();
      
      // Create a UserToken to identify which PrintTask is running.
      string myToken = "MY TOKEN2";
      
      // Use the 'synchronous geoprocessing task' PrintTask.ExecuteAsync Method.
      _PrintTask.ExecuteAsync(myPrintParameters, myToken);
      
      // Update the status informational messages.
      ListBox_StatusInformation.Items.Add("The PrintTask was started.");
    }
    else if (myMessage == MessageBoxResult.OK)
    {
      // The user has opted to let the currently runnning 'synchronous geoprocessing task' PrintTask complete. 
      
      // Update the status informational messages.
      ListBox_StatusInformation.Items.Add("The PrintTask is busy (still processing).");
    }
  }
  else if (_PrintTask.IsBusy == false)
  {
    // There is not and existing 'synchronous geoprocessing task' PrintTask running.
    
    // Clear out the status informational messages. 
    ListBox_StatusInformation.Items.Clear();
    
    // Create a UserToken to identify which PrintTask is running.
    string myToken = "MY TOKEN";
    
    // Use the 'synchronous geoprocessing task' PrintTask.ExecuteAsync Method.
    _PrintTask.ExecuteAsync(myPrintParameters, myToken);
    
    // Enable button for the user to cancel the PrintTask request.
    Button_CancelAsync.IsEnabled = true;
    
    // Update the status informational messages.
    ListBox_StatusInformation.Items.Add("The PrintTask was started.");
  }
}
            
private void printTask_ExecuteCompleted(object sender, ESRI.ArcGIS.Client.Printing.PrintEventArgs e)
{
  // Use only for ExecuteAsync operations (i.e. synchronous geoprocessing tasks).
  
  // Get any error information (add your own enhancements if desired). 
  System.Exception mySystemException = e.Error;
  
  // Get the PrintResult from the completed operation.
  ESRI.ArcGIS.Client.Printing.PrintResult myPrintResult = e.PrintResult;
  
  // Test is we have valid return PrintResults.
  if (myPrintResult != null)
  {
    // Get any messages returned from ArcGIS Server (add your own enhancements if desired).
    List<ESRI.ArcGIS.Client.Tasks.GPMessage> myListOfGPMessage = myPrintResult.Messages;
    
    // This is the userToken Parameter of the ExecuteAsync(printParameters,userToken)
    object myUserState = e.UserState;
    
    // Update the status informational messages.
    ListBox_StatusInformation.Items.Add("The PrintTask was completed for: " + myUserState.ToString());
    
    // Get the location of the image/.pdf created by ArcGIS Server.
    System.Uri myUri = myPrintResult.Url;
    
    // Open a new internet browser window with the generated image from the PrintTask.
    System.Windows.Browser.HtmlPage.Window.Navigate(myUri, "_blank");
  }
}
            
private void Button_CancelAsync_Click(object sender, System.Windows.RoutedEventArgs e)
{
  // This will cancel the ExecuteAsync operation. 
  _PrintTask.CancelAsync();
  
  // Update the status informational messages.
  ListBox_StatusInformation.Items.Add("The PrintTask was canceled.");
}

' Create a Global (aka. Member) variable for the PrintTask object that will be used in other 
' parts of the application.
Private _PrintTask As ESRI.ArcGIS.Client.Printing.PrintTask
            
Public Sub New()
  
  InitializeComponent()
  
  ' Provide a valid PrintTask.Url for a "synchronous geoprocessing task"
  TextBox_Url.Text = "http://localhost:6080/arcgis/rest/services/Utilities/PrintingTools/GPServer/Export20Web20Map%20Task"
  
  ' Set the _PrintTask variable to a new instance of the PrintTask Class.
  _PrintTask = New ESRI.ArcGIS.Client.Printing.PrintTask()
  
  ' Prevent the internet browser from using a cache for the PrintTask operations.
  _PrintTask.DisableClientCaching = True
  
  ' Set the PrintTask.Url from what is entered in the TextBox.
  _PrintTask.Url = TextBox_Url.Text
  
  ' Wire up an Event Handler for the PrintTask.ExecuteCompleted Event.
  AddHandler _PrintTask.ExecuteCompleted, AddressOf printTask_ExecuteCompleted
  
End Sub
            
Private Sub Button_ExecuteAsync_Click(sender As System.Object, e As System.Windows.RoutedEventArgs)
  
  ' Define the settings for rendering the image/.pdf on the ArcGIS Server.
  
  ' Define the ExportOptions.
  Dim myExportOptions As New ESRI.ArcGIS.Client.Printing.ExportOptions
  myExportOptions.Dpi = 96 '96 DPI is typical Window OS setting.
  myExportOptions.OutputSize = New Size(MyMap.ActualWidth, MyMap.ActualHeight) ' Use the dimensions of the Map
  
  ' Define the PrintParameters.
  Dim myPrintParameters As New ESRI.ArcGIS.Client.Printing.PrintParameters(MyMap)
  myPrintParameters.ExportOptions = myExportOptions ' Use the ExportOptions defined earlier.
  myPrintParameters.LayoutTemplate = "MAP_ONLY" ' Look to the REST service to see what layout templates are supported.
  myPrintParameters.Format = "JPG" ' Look to the REST service to see what image formats are supported.
  
  ' NOTE: 
  ' If you try to submit more that one 'synchronous geoprocessing task' via PrintTask.ExecuteAsync at a time 
  ' using the ExecuteAsync methadology you will get a Visual Studio (Runtime) error: 
  ' NotSupportedException was unhandled by user code. "Task does not support concurrent  I/O operations. Cancel 
  ' the pending request or wait for it to complete." 
  ' In order to overcome this, use the PrintTask.IsBusy Property and take action accordingly.
  
  If _PrintTask.IsBusy = True Then
    
    ' There is an existing 'synchronous geoprocessing task' PrintTask running. 
    
    ' Use a simple MessageBox to get user direction on whether to stay with the currently running 'synchronous 
    ' geoprocessing task' PrintTask or cancel it and start another one.
    Dim myMessage As System.Windows.MessageBoxResult =
     MessageBox.Show("Click 'Cancel' to kill the prior print job and print this one OR click 'OK' to finish the prior " +
                     "print job and wait to re-click the Print button.", "Action Required", MessageBoxButton.OKCancel)
    
    If myMessage = MessageBoxResult.Cancel Then
      
      ' The user has opted to cancel the currently runnning 'synchronous geoprocessing task' PrintTask. 
      
      ' Kill the PrintTask.
      _PrintTask.CancelAsync()
      
      ' Clear out the status informational messages. 
      ListBox_StatusInformation.Items.Clear()
      
      ' Create a UserToken to identify which PrintTask is running.
      Dim myToken As String = "MY TOKEN2"
      
      ' Use the 'synchronous geoprocessing task' PrintTask.ExecuteAsync Method.
      _PrintTask.ExecuteAsync(myPrintParameters, myToken)
      
      ' Update the status informational messages.
      ListBox_StatusInformation.Items.Add("The PrintTask was started.")
      
    ElseIf myMessage = MessageBoxResult.OK Then
      
      ' The user has opted to let the currently runnning 'synchronous geoprocessing task' PrintTask complete. 
      
      ' Update the status informational messages.
      ListBox_StatusInformation.Items.Add("The PrintTask is busy (still processing).")
      
    End If
      
  ElseIf _PrintTask.IsBusy = False Then
     
    ' There is not and existing 'synchronous geoprocessing task' PrintTask running.
    
    ' Clear out the status informational messages. 
    ListBox_StatusInformation.Items.Clear()
    
    ' Create a UserToken to identify which PrintTask is running.
    Dim myToken As String = "MY TOKEN"
    
    ' Use the 'synchronous geoprocessing task' PrintTask.ExecuteAsync Method.
    _PrintTask.ExecuteAsync(myPrintParameters, myToken)
    
    ' Enable button for the user to cancel the PrintTask request.
    Button_CancelAsync.IsEnabled = True
    
    ' Update the status informational messages.
    ListBox_StatusInformation.Items.Add("The PrintTask was started.")
    
  End If
    
End Sub
  
Private Sub printTask_ExecuteCompleted(sender As Object, e As ESRI.ArcGIS.Client.Printing.PrintEventArgs)
  
  ' Use only for ExecuteAsync operations (i.e. synchronous geoprocessing tasks).
  
  ' Get any error information (add your own enhancements if desired). 
  Dim mySystemException As System.Exception = e.Error
  
  ' Get the PrintResult from the completed operation.
  Dim myPrintResult As ESRI.ArcGIS.Client.Printing.PrintResult = e.PrintResult
  
  ' Test is we have valid return PrintResults.
  If myPrintResult IsNot Nothing Then
    
    ' Get any messages returned from ArcGIS Server (add your own enhancements if desired).
    Dim myListOfGPMessage As List(Of ESRI.ArcGIS.Client.Tasks.GPMessage) = myPrintResult.Messages
    
    ' This is the userToken Parameter of the ExecuteAsync(printParameters,userToken)
    Dim myUserState As Object = e.UserState
    
    ' Update the status informational messages.
    ListBox_StatusInformation.Items.Add("The PrintTask was completed for: " + myUserState)
    
    ' Get the location of the image/.pdf created by ArcGIS Server.
    Dim myUri As System.Uri = myPrintResult.Url
    
    ' Open a new internet browser window with the generated image from the PrintTask.
    System.Windows.Browser.HtmlPage.Window.Navigate(myUri, "_blank")
    
  End If
    
End Sub
            
Private Sub Button_CancelAsync_Click(sender As System.Object, e As System.Windows.RoutedEventArgs)
  
  ' This will cancel the ExecuteAsync operation. 
  _PrintTask.CancelAsync()
  
  ' Update the status informational messages.
  ListBox_StatusInformation.Items.Add("The PrintTask was canceled.")
            
End Sub