IReferenceService Interfaccia

Definizione

Fornisce un'interfaccia per ottenere riferimenti a oggetti di un progetto in base al nome o al tipo, ottenendo il nome di un oggetto specificato, e individuare l'elemento padre di un oggetto specificato in un progetto in modalità progettazione.

public interface IReferenceService

Esempio

Il controllo di esempio seguente usa il GetReferences metodo dell'interfaccia IReferenceService per ottenere un elenco di componenti nel progetto in modalità progettazione corrente del tipo del componente attualmente selezionato.

using System;
using System.Collections;
using System.ComponentModel;
using System.ComponentModel.Design;
using System.Drawing;
using System.Data;
using System.Windows.Forms;

namespace IReferenceServiceExample
{
    // This control displays the name and type of the primary selection 
    // component in design mode, if there is one,
    // and uses the IReferenceService interface to display the names of 
    // any components of the type of the primary selected component.    
    // This control uses the IComponentChangeService to monitor for 
    // selection changed events.
    public class IReferenceServiceControl : System.Windows.Forms.UserControl
    {
            // Indicates the name of the type of the selected component, or "None selected.".
            private string selected_typename;
            // Indicates the name of the base type of the selected component, or "None selected."
            private string selected_basetypename;
            // Indicates the name of the selected component.
            private string selected_componentname;
            // Contains the names of components of the type of the selected 
            // component in design mode.
            private string[] typeComponents;
            // Contains the names of components of the base type of the selected component in design mode.
            private string[] basetypeComponents;
            // Reference to the IComponentChangeService for the current component.
            private ISelectionService selectionService;
        
            public IReferenceServiceControl()
            {
                // Initializes the control properties.
                this.BackColor = Color.White;
                this.SetStyle(ControlStyles.ResizeRedraw, true);
                this.Name = "IReferenceServiceControl";
                this.Size = new System.Drawing.Size(500, 250);			                        
                // Initializes the data properties.
                typeComponents = new string[0];
                basetypeComponents = new string[0];
                selected_typename = "None selected.";
                selected_basetypename = "None selected.";
                selected_componentname = "None selected.";
                selectionService = null;
            }

            // Registers and unregisters design-mode services when 
            // the component is sited and unsited.
            public override System.ComponentModel.ISite Site
            {
                get
                {
                    // Returns the site for the control.
                    return base.Site;
                }
                set
                {
                    // The site is set to null when a component is cut or 
                    // removed from a design-mode site.

                    // If an event handler has already been linked with 
                    // an ISelectionService, remove the handler.
                    if(selectionService != null)
                        selectionService.SelectionChanged -= new EventHandler(this.OnSelectionChanged);

                    // Sites the control.
                    base.Site = value;
                
                    // Obtains an ISelectionService interface to register 
                    // the selection changed event handler with.
                    selectionService = (ISelectionService)this.GetService(typeof(ISelectionService));
                    if( selectionService!= null )
                    {
                        selectionService.SelectionChanged += new EventHandler(this.OnSelectionChanged);
                        // Updates the display for the current selection, if any.
                        DisplayComponentsOfSelectedComponentType();
                    }
                }
            }

            // Updates the display according to the primary selected component, 
            // if any, and the names of design-mode components that the 
            // IReferenceService returns references for when queried for 
            // references to components of the primary selected component's 
            // type and base type.
            private void DisplayComponentsOfSelectedComponentType()
            {
                // If a component is selected...
                if( selectionService.PrimarySelection != null )
                {              
                    // Sets the selected type name and selected component name to the type and name of the primary selected component.
                    selected_typename = selectionService.PrimarySelection.GetType().FullName;
                    selected_basetypename = selectionService.PrimarySelection.GetType().BaseType.FullName;
                    selected_componentname = ((IComponent)selectionService.PrimarySelection).Site.Name;                

                    // Obtain an IReferenceService and obtain references to 
                    // each component in the design-mode project
                    // of the selected component's type and base type.
                    IReferenceService rs = (IReferenceService)this.GetService(typeof(IReferenceService));
                    if( rs != null )
                    {
                        // Get references to design-mode components of the 
                        // primary selected component's type.
                        object[] comps = (object[])rs.GetReferences( selectionService.PrimarySelection.GetType() );
                        typeComponents = new string[comps.Length];
                        for(int i=0; i<comps.Length; i++)
                            typeComponents[i] = ((IComponent)comps[i]).Site.Name;
   
                        // Get references to design-mode components with a base type 
                        // of the primary selected component's base type.
                        comps = (object[])rs.GetReferences( selectionService.PrimarySelection.GetType().BaseType );
                        basetypeComponents = new string[comps.Length];
                        for(int i=0; i<comps.Length; i++)
                            basetypeComponents[i] = ((IComponent)comps[i]).Site.Name;
                    }
                }
                else
                {
                    selected_typename = "None selected.";
                    selected_basetypename = "None selected.";
                    selected_componentname = "None selected.";
                    typeComponents = new string[0];
                    basetypeComponents = new string[0];
                }
                this.Refresh();
            }

            private void OnSelectionChanged(object sender, EventArgs e)
            {
                DisplayComponentsOfSelectedComponentType();
            }

            protected override void OnPaint(System.Windows.Forms.PaintEventArgs e)
            {
                e.Graphics.DrawString("IReferenceService Example Control", new Font(FontFamily.GenericMonospace, 9), new SolidBrush(Color.Blue), 5, 5);

                e.Graphics.DrawString("Primary Selected Component from IComponentChangeService:", new Font(FontFamily.GenericMonospace, 8), new SolidBrush(Color.Red), 5, 20);
                e.Graphics.DrawString("Name:      "+selected_componentname, new Font(FontFamily.GenericMonospace, 8), new SolidBrush(Color.Black), 10, 32);
                e.Graphics.DrawString("Type:      "+selected_typename, new Font(FontFamily.GenericMonospace, 8), new SolidBrush(Color.Black), 10, 44);
                e.Graphics.DrawString("Base Type: "+selected_basetypename, new Font(FontFamily.GenericMonospace, 8), new SolidBrush(Color.Black), 10, 56);
                e.Graphics.DrawLine(new Pen(new SolidBrush(Color.Black), 1), 5, 77, this.Width-5, 77);
            
                e.Graphics.DrawString("Components of Type from IReferenceService:", new Font(FontFamily.GenericMonospace, 8), new SolidBrush(Color.Red), 5, 85);                        
                if( selected_typename != "None selected." )
                    for(int i=0; i<typeComponents.Length; i++)
                        e.Graphics.DrawString(typeComponents[i], new Font(FontFamily.GenericMonospace, 8), new SolidBrush(Color.Black), 20, 97+(i*12));
            
                e.Graphics.DrawString("Components of Base Type from IReferenceService:", new Font(FontFamily.GenericMonospace, 8), new SolidBrush(Color.Red), 5, 109+(typeComponents.Length*12));
                if( selected_typename != "None selected." )
                    for(int i=0; i<basetypeComponents.Length; i++)
                        e.Graphics.DrawString(basetypeComponents[i], new Font(FontFamily.GenericMonospace, 8), new SolidBrush(Color.Black), 20, 121+(typeComponents.Length*12)+(i*12));
            }
    }
}

Commenti

L'interfaccia IReferenceService fornisce i metodi seguenti:

  • Il GetReference metodo restituisce il componente con il nome specificato oppure null se non è stato trovato alcun componente con il nome specificato.

  • Il GetName metodo restituisce il nome associato al componente specificato.

  • Il GetComponent metodo restituisce il contenitore padre del componente specificato.

  • Il GetReferences metodo restituisce una matrice di riferimenti a tutti i componenti del progetto o a tutti i componenti di progetto di un tipo specificato facoltativamente.

Metodi

GetComponent(Object)

Ottiene il componente che contiene il componente specificato.

GetName(Object)

Ottiene il nome del componente specificato.

GetReference(String)

Ottiene un riferimento al componente il cui nome corrisponde al nome specificato.

GetReferences()

Ottiene tutti i riferimenti disponibili ai componenti del progetto.

GetReferences(Type)

Ottiene tutti i riferimenti disponibili ai componenti del tipo specificato.

Si applica a

Prodotto Versioni
.NET Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 2.0, 2.1