ToolboxItemCreatorCallback Delegate
Represents the method that will handle the ToolboxItemCreatorCallback event.
[Visual Basic] <Serializable> Public Delegate Function Sub ToolboxItemCreatorCallback( _ ByVal serializedObject As Object, _ ByVal format As String _ ) As ToolboxItem [C#] [Serializable] public delegate ToolboxItem ToolboxItemCreatorCallback( object serializedObject, string format ); [C++] [Serializable] public __gc __delegate ToolboxItem* ToolboxItemCreatorCallback( Object* serializedObject, String* format );
[JScript] In JScript, you can use the delegates in the .NET Framework, but you cannot define your own.
Parameters [Visual Basic, C#, C++]
The declaration of your callback method must have the same parameters as the ToolboxItemCreatorCallback delegate declaration.
- serializedObject
- The object which contains the data to create a ToolboxItem for.
- format
- The name of the clipboard data format to create a ToolboxItem for.
Remarks
You can implement a toolbox item creator method with a method signature matching the method signature of this delegate type that creates a toolbox item from any object of a particular clipboard data format placed on the toolbox. For example, you can design a toolbox item creator that creates a TextBox to store text pasted to the toolbox from the clipboard. You can use the AddCreator method of the IToolboxService to add a ToolboxItemCreatorCallback event handler for a particular data type to the toolbox. The serializedObject parameter contains the data object.
When you create a ToolboxItemCreatorCallback delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event handler delegates, see Events and Delegates.
Example
[Visual Basic, C#, C++] The following example provides a component that uses the IToolboxService to add a "Text" data format handler, or ToolboxItemCreatorCallback, to the toolbox. The data creator callback delegate passes any text data pasted to the toolbox and dragged onto a form to a custom ToolboxItem that creates a System.Windows.Forms.TextBox containing the text.
[Visual Basic] Imports System Imports System.ComponentModel Imports System.ComponentModel.Design Imports System.Drawing Imports System.Drawing.Design Imports System.Windows.Forms ' Component that adds a "Text" data format ToolboxItemCreatorCallback ' to the Toolbox that creates a custom ToolboxItem that ' creates a TextBox containing the text data. Public Class TextDataTextBoxComponent Inherits System.ComponentModel.Component Private creatorAdded As Boolean = False Private ts As IToolboxService Public Sub New() End Sub ' ISite override to register TextBox creator Public Overrides Property Site() As System.ComponentModel.ISite Get Return MyBase.Site End Get Set(ByVal Value As System.ComponentModel.ISite) If Not (Value Is Nothing) Then MyBase.Site = Value If Not creatorAdded Then AddTextTextBoxCreator() End If Else If creatorAdded Then RemoveTextTextBoxCreator() End If MyBase.Site = Value End If End Set End Property ' Adds a "Text" data format creator to the toolbox that creates ' a textbox from a text fragment pasted to the toolbox. Private Sub AddTextTextBoxCreator() ts = CType(GetService(GetType(IToolboxService)), IToolboxService) If Not (ts Is Nothing) Then Dim textCreator As New ToolboxItemCreatorCallback(AddressOf Me.CreateTextBoxForText) Try ts.AddCreator(textCreator, "Text", CType(GetService(GetType(IDesignerHost)), IDesignerHost)) creatorAdded = True Catch ex As Exception MessageBox.Show(ex.ToString(), "Exception Information") End Try End If End Sub ' Removes any "Text" data format creator from the toolbox. Private Sub RemoveTextTextBoxCreator() If Not (ts Is Nothing) Then ts.RemoveCreator("Text", CType(GetService(GetType(IDesignerHost)), IDesignerHost)) creatorAdded = False End If End Sub ' ToolboxItemCreatorCallback delegate format method to create ' the toolbox item. Private Function CreateTextBoxForText(ByVal serializedObject As Object, ByVal format As String) As ToolboxItem Dim formats As String() = CType(serializedObject, System.Windows.Forms.DataObject).GetFormats() If CType(serializedObject, System.Windows.Forms.DataObject).GetDataPresent("System.String", True) Then Return New TextToolboxItem(CStr(CType(serializedObject, System.Windows.Forms.DataObject).GetData("System.String", True))) End If Return Nothing End Function Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean) If creatorAdded Then RemoveTextTextBoxCreator() End If End Sub End Class ' Custom toolbox item creates a TextBox and sets its Text property ' to the constructor-specified text. Public Class TextToolboxItem Inherits System.Drawing.Design.ToolboxItem Private [text] As String Delegate Sub SetTextMethodHandler(ByVal c As Control, ByVal [text] As String) Public Sub New(ByVal [text] As String) Me.text = [text] End Sub ' ToolboxItem.CreateComponentsCore override to create the TextBox ' and link a method to set its Text property. <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _ Protected Overrides Function CreateComponentsCore(ByVal host As System.ComponentModel.Design.IDesignerHost) As System.ComponentModel.IComponent() Dim textbox As System.Windows.Forms.TextBox = CType(host.CreateComponent(GetType(TextBox)), TextBox) ' Because the designer resets the text of the textbox, use ' a SetTextMethodHandler to set the text to the value of ' the text data. Dim c As Control = host.RootComponent c.BeginInvoke(New SetTextMethodHandler(AddressOf OnSetText), New Object() {textbox, [text]}) Return New System.ComponentModel.IComponent() {textbox} End Function ' Method to set the text property of a TextBox after it is initialized. Private Sub OnSetText(ByVal c As Control, ByVal [text] As String) c.Text = [text] End Sub End Class [C#] using System; using System.ComponentModel; using System.ComponentModel.Design; using System.Drawing; using System.Drawing.Design; using System.Windows.Forms; namespace TextDataTextBoxComponent { // Component that adds a "Text" data format ToolboxItemCreatorCallback // to the Toolbox that creates a custom ToolboxItem that // creates a TextBox containing the text data. public class TextDataTextBoxComponent : System.ComponentModel.Component { private bool creatorAdded = false; private IToolboxService ts; public TextDataTextBoxComponent() { } // ISite override to register TextBox creator public override System.ComponentModel.ISite Site { get { return base.Site; } set { if( value != null ) { base.Site = value; if( !creatorAdded ) AddTextTextBoxCreator(); } else { if( creatorAdded ) RemoveTextTextBoxCreator(); base.Site = value; } } } // Adds a "Text" data format creator to the toolbox that creates // a textbox from a text fragment pasted to the toolbox. private void AddTextTextBoxCreator() { ts = (IToolboxService)GetService(typeof(IToolboxService)); if (ts != null) { ToolboxItemCreatorCallback textCreator = new ToolboxItemCreatorCallback(this.CreateTextBoxForText); try { ts.AddCreator(textCreator, "Text", (IDesignerHost)GetService(typeof(IDesignerHost))); creatorAdded = true; } catch(Exception ex) { MessageBox.Show(ex.ToString(), "Exception Information"); } } } // Removes any "Text" data format creator from the toolbox. private void RemoveTextTextBoxCreator() { if (ts != null) { ts.RemoveCreator("Text", (IDesignerHost)GetService(typeof(IDesignerHost))); creatorAdded = false; } } // ToolboxItemCreatorCallback delegate format method to create // the toolbox item. private ToolboxItem CreateTextBoxForText(object serializedObject, string format) { string[] formats = ((System.Windows.Forms.DataObject)serializedObject).GetFormats(); if( ((System.Windows.Forms.DataObject)serializedObject).GetDataPresent("System.String", true) ) return new TextToolboxItem( (string)((System.Windows.Forms.DataObject)serializedObject).GetData("System.String", true) ); return null; } protected override void Dispose(bool disposing) { if( creatorAdded ) RemoveTextTextBoxCreator(); } } // Custom toolbox item creates a TextBox and sets its Text property // to the constructor-specified text. public class TextToolboxItem : System.Drawing.Design.ToolboxItem { private string text; private delegate void SetTextMethodHandler(Control c, string text); public TextToolboxItem(string text) : base() { this.text = text; } // ToolboxItem.CreateComponentsCore override to create the TextBox // and link a method to set its Text property. [System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")] protected override System.ComponentModel.IComponent[] CreateComponentsCore(System.ComponentModel.Design.IDesignerHost host) { System.Windows.Forms.TextBox textbox = (TextBox)host.CreateComponent(typeof(TextBox)); // Because the designer resets the text of the textbox, use // a SetTextMethodHandler to set the text to the value of // the text data. Control c = host.RootComponent as Control; c.BeginInvoke(new SetTextMethodHandler(OnSetText), new object[] {textbox, text}); return new System.ComponentModel.IComponent[] { textbox }; } // Method to set the text property of a TextBox after it is initialized. private void OnSetText(Control c, string text) { c.Text = text; } } } [C++] #using <mscorlib.dll> #using <System.Windows.Forms.dll> #using <System.Drawing.dll> #using <System.dll> using namespace System; using namespace System::ComponentModel; using namespace System::ComponentModel::Design; using namespace System::Drawing; using namespace System::Drawing::Design; using namespace System::Windows::Forms; namespace TextDataTextBoxComponent { // Custom toolbox item creates a TextBox and sets its Text property // to the constructor-specified text. public __gc class TextToolboxItem : public System::Drawing::Design::ToolboxItem { private: String* text; __delegate void SetTextMethodHandler(Control* c, String* text); public: TextToolboxItem(String* text) : ToolboxItem() { this->text = text; } // ToolboxItem::CreateComponentsCore to create the TextBox // and link a method to set its Text property. protected: [System::Security::Permissions::PermissionSet(System::Security::Permissions::SecurityAction::Demand, Name="FullTrust")] System::ComponentModel::IComponent* CreateComponentsCore(System::ComponentModel::Design::IDesignerHost* host)[] { System::Windows::Forms::TextBox* textbox = dynamic_cast<TextBox*>(host->CreateComponent(__typeof(TextBox))); // Because the designer resets the text of the textbox, use // a SetTextMethodHandler to set the text to the value of // the text data. Control* c = dynamic_cast<Control*>(host->RootComponent); Object* temp0 [] = {textbox, text}; c->BeginInvoke(new SetTextMethodHandler(this, &TextToolboxItem::OnSetText), temp0); System::ComponentModel::IComponent* temp1 [] = {textbox}; return temp1; } // Method to set the text property of a TextBox after it is initialized. private: void OnSetText(Control* c, String* text) { c->Text = text; } }; // Component that adds a "Text" data format ToolboxItemCreatorCallback // to the Toolbox that creates a custom ToolboxItem that // creates a TextBox containing the text data. public __gc class TextDataTextBoxComponent : public System::ComponentModel::Component { private: bool creatorAdded; IToolboxService* ts; public: TextDataTextBoxComponent() { creatorAdded = false; } // ISite to register TextBox creator __property System::ComponentModel::ISite* get_Site() { return Component::get_Site(); } __property void set_Site(System::ComponentModel::ISite* value) { if (value != 0) { Component::set_Site(value); if (!creatorAdded) AddTextTextBoxCreator(); } else { if (creatorAdded) RemoveTextTextBoxCreator(); Component::set_Site(value); } } // Adds a "Text" data format creator to the toolbox that creates // a textbox from a text fragment pasted to the toolbox. private: void AddTextTextBoxCreator() { ts = dynamic_cast<IToolboxService*>(GetService(__typeof(IToolboxService))); if (ts != 0) { ToolboxItemCreatorCallback* textCreator = new ToolboxItemCreatorCallback(this, &TextDataTextBoxComponent::CreateTextBoxForText); try { ts->AddCreator(textCreator, S"Text", dynamic_cast<IDesignerHost*>(GetService(__typeof(IDesignerHost)))); creatorAdded = true; } catch (Exception* ex) { MessageBox::Show(ex->ToString(), S"Exception Information"); } } } // Removes any "Text" data format creator from the toolbox. void RemoveTextTextBoxCreator() { if (ts != 0) { ts->RemoveCreator(S"Text", dynamic_cast<IDesignerHost*>(GetService(__typeof(IDesignerHost)))); creatorAdded = false; } } // ToolboxItemCreatorCallback delegate format method to create // the toolbox item. ToolboxItem* CreateTextBoxForText(Object* serializedObject, String* format) { String* formats[] = (dynamic_cast<System::Windows::Forms::DataObject*>(serializedObject))->GetFormats(); if ((dynamic_cast<System::Windows::Forms::DataObject*>(serializedObject))->GetDataPresent(S"System::String", true)) return new TextToolboxItem(dynamic_cast<String*>((dynamic_cast<System::Windows::Forms::DataObject*>(serializedObject))->GetData(S"System::String", true))); return 0; } protected: void Dispose(bool disposing) { if (creatorAdded) RemoveTextTextBoxCreator(); } }; }
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Requirements
Namespace: System.Drawing.Design
Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family
Assembly: System.Drawing (in System.Drawing.dll)