IReferenceService Interface

Definition

Provides an interface for obtaining references to objects within a project by name or type, obtaining the name of a specified object, and for locating the parent of a specified object within a designer project.

C#
public interface IReferenceService

Examples

The following example control uses the GetReferences method of the IReferenceService interface to obtain a list of components in the current design mode project of the type of the currently selected component.

C#
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));
            }
    }
}

Remarks

The IReferenceService interface provides the following methods:

  • The GetReference method returns the component with the specified name, or null if no component with the specified name was found.

  • The GetName method returns the name associated with the specified component.

  • The GetComponent method returns the parent container of the specified component.

  • The GetReferences method returns an array of references to all project components, or all project components of an optionally specified type.

Methods

GetComponent(Object)

Gets the component that contains the specified component.

GetName(Object)

Gets the name of the specified component.

GetReference(String)

Gets a reference to the component whose name matches the specified name.

GetReferences()

Gets all available references to project components.

GetReferences(Type)

Gets all available references to components of the specified type.

Applies to

Product Versions
.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