ServiceContainer Class

 

Provides a simple implementation of the IServiceContainer interface. This class cannot be inherited.

Namespace:   System.ComponentModel.Design
Assembly:  System (in System.dll)

System::Object
  System.ComponentModel.Design::ServiceContainer

[HostProtectionAttribute(SecurityAction::LinkDemand, SharedState = true)]
public ref class ServiceContainer : IServiceContainer, IServiceProvider, 
	IDisposable

NameDescription
System_CAPS_pubmethodServiceContainer()

Initializes a new instance of the ServiceContainer class.

System_CAPS_pubmethodServiceContainer(IServiceProvider^)

Initializes a new instance of the ServiceContainer class using the specified parent service provider.

NameDescription
System_CAPS_protpropertyDefaultServices

Gets the default services implemented directly by ServiceContainer.

NameDescription
System_CAPS_pubmethodAddService(Type^, Object^)

Adds the specified service to the service container.

System_CAPS_pubmethodAddService(Type^, Object^, Boolean)

Adds the specified service to the service container.

System_CAPS_pubmethodAddService(Type^, ServiceCreatorCallback^)

Adds the specified service to the service container.

System_CAPS_pubmethodAddService(Type^, ServiceCreatorCallback^, Boolean)

Adds the specified service to the service container.

System_CAPS_pubmethodDispose()

Disposes this service container.

System_CAPS_protmethodDispose(Boolean)

Disposes this service container.

System_CAPS_pubmethodEquals(Object^)

Determines whether the specified object is equal to the current object.(Inherited from Object.)

System_CAPS_protmethodFinalize()

Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.)

System_CAPS_pubmethodGetHashCode()

Serves as the default hash function. (Inherited from Object.)

System_CAPS_pubmethodGetService(Type^)

Gets the requested service.

System_CAPS_pubmethodGetType()

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_protmethodMemberwiseClone()

Creates a shallow copy of the current Object.(Inherited from Object.)

System_CAPS_pubmethodRemoveService(Type^)

Removes the specified service type from the service container.

System_CAPS_pubmethodRemoveService(Type^, Boolean)

Removes the specified service type from the service container.

System_CAPS_pubmethodToString()

Returns a string that represents the current object.(Inherited from Object.)

The ServiceContainer object can be used to store and provide services. ServiceContainer implements the IServiceContainer interface.

The ServiceContainer object can be created using a constructor that adds a parent IServiceContainer through which services can be optionally added to or removed from all parent IServiceContainer objects, including the immediate parent IServiceContainer. To add or remove a service from all IServiceContainer implementations that are linked to this IServiceContainer through parenting, call the AddService or RemoveService method overload that accepts a Boolean value indicating whether to promote the service request.

System_CAPS_noteNote

The HostProtectionAttribute attribute applied to this class has the following Resources property value: SharedState. The HostProtectionAttribute does not affect desktop applications (which are typically started by double-clicking an icon, typing a command, or entering a URL in a browser). For more information, see the HostProtectionAttribute class or SQL Server Programming and Host Protection Attributes.

The following example program demonstrates service chaining and the resultant service availability of a chain of linked ServiceContainer objects. The program provides a user interface that allows you to see the availability of services within a chain of linked services, and uses the AddService, GetService, and RemoveService methods as well as linked service containers.

#using <System.Windows.Forms.dll>
#using <System.dll>
#using <System.Drawing.dll>

using namespace System;
using namespace System::Drawing;
using namespace System::Collections;
using namespace System::ComponentModel;
using namespace System::ComponentModel::Design;
using namespace System::Windows::Forms;
using namespace System::Windows::Forms::Design;

ref class ServiceObjectControl;

// Example form provides UI for demonstrating service sharing behavior
// of a network of IServiceContainer/IServiceProvider controls.
public ref class ServiceForm: public System::Windows::Forms::Form
{
private:

   // Root service container control for tree.
   ServiceObjectControl^ root;

   // Button for clearing any provided services and resetting tree states.
   System::Windows::Forms::Button^ reset_button;

   // Color list used to color code controls.
   array<Color>^colorkeys;

   // Strings used to reflect text service.
   array<String^>^keystrings;

public:
   ServiceForm()
   {
      InitializeComponent();
      CreateServiceControlTree();
      colorkeys = gcnew array<Color>(6);
      colorkeys[ 0 ] = Color::Beige;
      colorkeys[ 1 ] = Color::SeaShell;
      colorkeys[ 2 ] = Color::LightGreen;
      colorkeys[ 3 ] = Color::LightBlue;
      colorkeys[ 4 ] = Color::Khaki;
      colorkeys[ 5 ] = Color::CadetBlue;
      array<String^>^stringstemp = {"No service use","Service not accessible","Service provided",
            "Service obtained","Service accessible","No further access"};
      keystrings = stringstemp;
   }

private:
   void CreateServiceControlTree();
   void InitializeComponent();

internal:
   void ResetServiceTree( Object^ sender, EventArgs^ e );
public:
   void UpdateServiceCoverage();

protected:
   virtual void OnPaint( System::Windows::Forms::PaintEventArgs^ e ) override;
};

// Example service type contains a text string, sufficient
// to demonstrate service sharing.
public ref class TextService
{
public:
   String^ text;
   TextService()
      : text( String::Empty )
   {}

   TextService( String^ text )
   {
      this->text = text;
   }
};

public enum class TextServiceState
{
   ServiceNotObtained, ServiceObtained, ServiceProvided, ServiceNotFound
};

// Example Form for entering a string.
private ref class StringInputDialog: public System::Windows::Forms::Form
{
private:
   System::Windows::Forms::Button^ ok_button;
   System::Windows::Forms::Button^ cancel_button;

public:
   System::Windows::Forms::TextBox^ inputTextBox;
   StringInputDialog( String^ text )
   {
      InitializeComponent();
      inputTextBox->Text = text;
   }

private:
   void InitializeComponent()
   {
      this->ok_button = gcnew System::Windows::Forms::Button;
      this->cancel_button = gcnew System::Windows::Forms::Button;
      this->inputTextBox = gcnew System::Windows::Forms::TextBox;
      this->SuspendLayout();
      this->ok_button->Anchor = static_cast<AnchorStyles>(System::Windows::Forms::AnchorStyles::Bottom |
            System::Windows::Forms::AnchorStyles::Right);
      this->ok_button->Location = System::Drawing::Point( 180, 43 );
      this->ok_button->Name = "ok_button";
      this->ok_button->TabIndex = 1;
      this->ok_button->Text = "OK";
      this->ok_button->DialogResult = System::Windows::Forms::DialogResult::OK;
      this->cancel_button->Anchor = static_cast<AnchorStyles>(System::Windows::Forms::AnchorStyles::Bottom |
            System::Windows::Forms::AnchorStyles::Right);
      this->cancel_button->Location = System::Drawing::Point( 260, 43 );
      this->cancel_button->Name = "cancel_button";
      this->cancel_button->TabIndex = 2;
      this->cancel_button->Text = "Cancel";
      this->cancel_button->DialogResult = System::Windows::Forms::DialogResult::Cancel;
      this->inputTextBox->Location = System::Drawing::Point( 6, 9 );
      this->inputTextBox->Name = "inputTextBox";
      this->inputTextBox->Size = System::Drawing::Size( 327, 20 );
      this->inputTextBox->TabIndex = 0;
      this->inputTextBox->Text = "";
      this->inputTextBox->Anchor = static_cast<AnchorStyles>((System::Windows::Forms::AnchorStyles::Top |
            System::Windows::Forms::AnchorStyles::Left) | System::Windows::Forms::AnchorStyles::Right);
      this->ClientSize = System::Drawing::Size( 342, 73 );
      array<System::Windows::Forms::Control^>^temp0 = {this->inputTextBox,this->cancel_button,this->ok_button};
      this->Controls->AddRange( temp0 );
      this->MinimumSize = System::Drawing::Size( 350, 100 );
      this->Name = "StringInputDialog";
      this->Text = "Text Service Provide String Dialog";
      this->ResumeLayout( false );
   }
};


// An example user control that uses ServiceContainer to add, remove,
// and access services through a linkable service container network.
public ref class ServiceObjectControl: public System::Windows::Forms::UserControl
{
public:

   // This example user control implementation provides a wrapper for
   // ServiceContainer, supporting a linked service container network.
   ServiceContainer^ serviceContainer;

private:

   // Parent form reference for main program function access.
   ServiceForm^ parent;

public:

   // String for label displayed on the control to indicate the
   // control's current service-related configuration state.
   String^ label;

private:

   // The current state of the control reflecting whether it has
   // obtained or provided a text service.
   TextServiceState state_;

public:

   property TextServiceState state 
   {
      TextServiceState get()
      {
         return state_;
      }

      void set( TextServiceState value )
      {
         if ( (TextServiceState)value == TextServiceState::ServiceProvided )
                  this->BackColor = Color::LightGreen;
         else
         if ( (TextServiceState)value == TextServiceState::ServiceNotObtained )
                  this->BackColor = Color::White;
         else
         if ( (TextServiceState)value == TextServiceState::ServiceObtained )
                  this->BackColor = Color::LightBlue;
         else
         if ( (TextServiceState)value == TextServiceState::ServiceNotFound )
                  this->BackColor = Color::SeaShell;

         state_ = value;
      }
   }
   ServiceObjectControl( ServiceObjectControl^ serviceContainerParent, System::Drawing::Size size,
         Point location, ServiceForm^ parent )
   {
      this->state_ = TextServiceState::ServiceNotObtained;
      this->BackColor = Color::Beige;
      this->label = String::Empty;
      this->Size = size;
      this->Location = location;
      this->parent = parent;
      if ( serviceContainerParent == nullptr )
            serviceContainer = gcnew ServiceContainer;
      else
            serviceContainer = gcnew ServiceContainer( serviceContainerParent->serviceContainer );
   }

protected:

   // Paint method override draws the label string on the control.
   virtual void OnPaint( System::Windows::Forms::PaintEventArgs^ e ) override
   {
      e->Graphics->DrawString( label, gcnew System::Drawing::Font( "Arial",8 ), gcnew SolidBrush( Color::Black ), 5, 5 );
   }

   // Process mouse-down behavior for click.
   virtual void OnMouseDown( System::Windows::Forms::MouseEventArgs^ e ) override
   {
      if ( e->Button == ::MouseButtons::Left )
      {
         if ( state_ != TextServiceState::ServiceProvided )
         {
            // Attempt to update text from service, and set color
            // state accordingly.
            TextService^ ts = dynamic_cast<TextService^>(serviceContainer->GetService( TextService::typeid ));
            if ( ts != nullptr )
            {
               this->label = ts->text;
               state = TextServiceState::ServiceObtained;
            }
            else
            {
               this->label = "Service Not Found";
               state = TextServiceState::ServiceNotFound;
            }
         }
      }

      if ( e->Button == ::MouseButtons::Right )
      {
         if ( state_ == TextServiceState::ServiceProvided )
         {
            // Remove service if the container provided it.
            if ( serviceContainer->GetService( TextService::typeid ) != nullptr )
            {
               serviceContainer->RemoveService( TextService::typeid, true );
               state = TextServiceState::ServiceNotObtained;
               this->label = "Service Removed";
            }
         }
         else
         {
            // Obtain string and provide text service.
            StringInputDialog^ form = gcnew StringInputDialog( "Test String" );
            form->StartPosition = FormStartPosition::CenterParent;
            if ( form->ShowDialog() == DialogResult::OK )
            {
               if ( serviceContainer->GetService( TextService::typeid ) != nullptr )
                              serviceContainer->RemoveService( TextService::typeid, true );
               parent->ResetServiceTree( this, gcnew EventArgs );
               serviceContainer->AddService( TextService::typeid, gcnew TextService( form->inputTextBox->Text ), true );
               state = TextServiceState::ServiceProvided;
               this->label = String::Format( "Provided Text: {0}", form->inputTextBox->Text );
            }
         }
      }

      parent->UpdateServiceCoverage();
   }

public:

   // Method accesses the TextService to test the visibility of the service
   // from the control, and sets the UI state accordingly.
   void ReflectServiceVisibility()
   {
      if ( state_ == TextServiceState::ServiceObtained )
      {
         if ( serviceContainer->GetService( TextService::typeid ) == nullptr )
                  this->BackColor = Color::CadetBlue;
      }
      else
      if ( state_ != TextServiceState::ServiceProvided )
      {
         if ( serviceContainer->GetService( TextService::typeid ) == nullptr )
         {
            this->BackColor = Color::White;
            return;
         }

         // Service available.
         if ( state_ == TextServiceState::ServiceNotFound )
                  this->BackColor = Color::Khaki;
         else
         if ( state_ == TextServiceState::ServiceNotObtained &&  !label->Equals( "Service Removed" ) )
                  this->BackColor = Color::Khaki;
      }
   }
};

void ServiceForm::CreateServiceControlTree()
{
   // Create root service control.
   ServiceObjectControl^ control1 = gcnew ServiceObjectControl( nullptr,System::Drawing::Size( 300, 40 ),Point(10,80),this );
   root = control1;

   // Create first tier - pass parent with service object control 1
   ServiceObjectControl^ control2 = gcnew ServiceObjectControl( control1,System::Drawing::Size( 200, 30 ),Point(50,160),this );
   ServiceObjectControl^ control3 = gcnew ServiceObjectControl( control1,System::Drawing::Size( 200, 30 ),Point(50,240),this );

   // Create second tier A - pass parent with service object control 2
   ServiceObjectControl^ control4 = gcnew ServiceObjectControl( control2,System::Drawing::Size( 180, 20 ),Point(300,145),this );
   ServiceObjectControl^ control5 = gcnew ServiceObjectControl( control2,System::Drawing::Size( 180, 20 ),Point(300,185),this );

   // Create second tier B - pass parent with service object control 3
   ServiceObjectControl^ control6 = gcnew ServiceObjectControl( control3,System::Drawing::Size( 180, 20 ),Point(300,225),this );
   ServiceObjectControl^ control7 = gcnew ServiceObjectControl( control3,System::Drawing::Size( 180, 20 ),Point(300,265),this );

   // Add controls.
   array<Control^>^temp1 = {control1,control2,control3,control4,control5,control6,control7};
   this->Controls->AddRange( temp1 );
}

void ServiceForm::ResetServiceTree( Object^ /*sender*/, EventArgs^ /*e*/ )
{
   // Remove the service from the service tree.
   if ( root->serviceContainer->GetService( TextService::typeid ) != nullptr )
      root->serviceContainer->RemoveService( TextService::typeid, true );

   // Set all controls to "not obtained" and clear their labels.
   for ( int i = 0; i < Controls->Count; i++ )
      if (  !Controls[ i ]->Equals( reset_button ) )
      {
         (dynamic_cast<ServiceObjectControl^>(Controls[ i ]))->state = TextServiceState::ServiceNotObtained;
         (dynamic_cast<ServiceObjectControl^>(Controls[ i ]))->label = String::Empty;
         (dynamic_cast<ServiceObjectControl^>(Controls[ i ]))->BackColor = Color::Beige;
      }
}

void ServiceForm::UpdateServiceCoverage()
{
   // Have each control set state to reflect service availability.
   for ( int i = 0; i < Controls->Count; i++ )
      if (  !Controls[ i ]->Equals( reset_button ) )
            (dynamic_cast<ServiceObjectControl^>(Controls[ i ]))->ReflectServiceVisibility();
}

void ServiceForm::InitializeComponent()
{
   this->reset_button = gcnew System::Windows::Forms::Button;
   this->SuspendLayout();

   //
   // reset_button
   //
   this->reset_button->Location = System::Drawing::Point( 392, 88 );
   this->reset_button->Name = "reset_button";
   this->reset_button->TabIndex = 0;
   this->reset_button->TabStop = false;
   this->reset_button->Text = "Reset";
   this->reset_button->Click += gcnew System::EventHandler( this, &ServiceForm::ResetServiceTree );

   //
   // ServiceForm
   //
   this->ClientSize = System::Drawing::Size( 512, 373 );
   array<System::Windows::Forms::Control^>^temp2 = {this->reset_button};
   this->Controls->AddRange( temp2 );
   this->MinimumSize = System::Drawing::Size( 520, 400 );
   this->Name = "ServiceForm";
   this->Text = "Service Container Architecture Example";
   this->ResumeLayout( false );
}

void ServiceForm::OnPaint( System::Windows::Forms::PaintEventArgs^ e )
{
   e->Graphics->DrawString( "The following tree diagram represents a hierarchy of linked service containers in controls.",
         gcnew System::Drawing::Font( "Arial",9 ), gcnew SolidBrush( Color::Black ), 4, 4 );
   e->Graphics->DrawString( "This example demonstrates the propagation behavior of services through a linked service object tree.",
         gcnew System::Drawing::Font( "Arial",8 ), gcnew SolidBrush( Color::Black ), 4, 26 );
   e->Graphics->DrawString( "Right-click a component to add or replace a text service, or to remove it if the component provided it.",
         gcnew System::Drawing::Font( "Arial",8 ), gcnew SolidBrush( Color::Black ), 4, 38 );
   e->Graphics->DrawString( "Left-click a component to update text from the text service if available.",
         gcnew System::Drawing::Font( "Arial",8 ), gcnew SolidBrush( Color::Black ), 4, 50 );

   // Draw lines to represent tree branches.
   e->Graphics->DrawLine( gcnew Pen( gcnew SolidBrush( Color::Black ),1 ), 20, 125, 20, 258 );
   e->Graphics->DrawLine( gcnew Pen( gcnew SolidBrush( Color::Black ),1 ), 21, 175, 45, 175 );
   e->Graphics->DrawLine( gcnew Pen( gcnew SolidBrush( Color::Black ),1 ), 21, 258, 45, 258 );
   e->Graphics->DrawLine( gcnew Pen( gcnew SolidBrush( Color::Black ),1 ), 255, 175, 285, 175 );
   e->Graphics->DrawLine( gcnew Pen( gcnew SolidBrush( Color::Black ),1 ), 255, 258, 285, 258 );
   e->Graphics->DrawLine( gcnew Pen( gcnew SolidBrush( Color::Black ),1 ), 285, 155, 285, 195 );
   e->Graphics->DrawLine( gcnew Pen( gcnew SolidBrush( Color::Black ),1 ), 285, 238, 285, 278 );
   e->Graphics->DrawLine( gcnew Pen( gcnew SolidBrush( Color::Black ),1 ), 285, 155, 290, 155 );
   e->Graphics->DrawLine( gcnew Pen( gcnew SolidBrush( Color::Black ),1 ), 285, 195, 290, 195 );
   e->Graphics->DrawLine( gcnew Pen( gcnew SolidBrush( Color::Black ),1 ), 285, 238, 290, 238 );
   e->Graphics->DrawLine( gcnew Pen( gcnew SolidBrush( Color::Black ),1 ), 285, 278, 290, 278 );

   // Draw color key.
   e->Graphics->DrawRectangle( gcnew Pen( gcnew SolidBrush( Color::Black ),1 ), 20, 305, 410, 60 );
   int y = 0;
   for ( int i = 0; i < 3; i++ )
   {
      e->Graphics->FillRectangle( gcnew SolidBrush( colorkeys[ y ] ), 25 + (i * 140), 310, 20, 20 );
      e->Graphics->DrawRectangle( gcnew Pen( gcnew SolidBrush( Color::Black ),1 ), 25 + (i * 140), 310, 20, 20 );
      e->Graphics->DrawString( keystrings[ y ], gcnew System::Drawing::Font( "Arial",8 ), gcnew SolidBrush( Color::Black ),
            (float)50 + (i * 140), 315 );
      y++;
      e->Graphics->FillRectangle( gcnew SolidBrush( colorkeys[ y ] ), 25 + (i * 140), 340, 20, 20 );
      e->Graphics->DrawRectangle( gcnew Pen( gcnew SolidBrush( Color::Black ),1 ), 25 + (i * 140), 340, 20, 20 );
      e->Graphics->DrawString( keystrings[ y ], gcnew System::Drawing::Font( "Arial",8 ), gcnew SolidBrush( Color::Black ),
            (float)50 + (i * 140), 345 );
      y++;
   }
}

[STAThread]
int main()
{
   Application::Run( gcnew ServiceForm );
}

.NET Framework
Available since 1.1

Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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