ComponentEditor 类

定义

命名空间:

System.ComponentModel

程序集:

System.ComponentModel.TypeConverter.dll

Source:

BaseComponentEditor.cs

提供自定义组件编辑器的基类。

public ref class ComponentEditor abstract

public abstract class ComponentEditor

type ComponentEditor = class

Public MustInherit Class ComponentEditor

继承

Object

ComponentEditor

派生

System.Windows.Forms.Design.WindowsFormsComponentEditor

示例

下面的代码示例演示了一个示例 ComponentEditor 实现。

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

// This example demonstrates how to implement a component editor that hosts 
// component pages and associate it with a component. This example also 
// demonstrates how to implement a component page that provides a panel-based 
// control system and Help keyword support.
namespace ComponentEditorExample
{
    // The ExampleComponentEditor displays two ExampleComponentEditorPage pages.
    public class ExampleComponentEditor : System.Windows.Forms.Design.WindowsFormsComponentEditor
    {
        // This method override returns an type array containing the type of 
        // each component editor page to display.
        protected override Type[] GetComponentEditorPages()
        {
            return new Type[] { typeof(ExampleComponentEditorPage),
                                typeof(ExampleComponentEditorPage) };
        }

        // This method override returns the index of the page to display when the 
        // component editor is first displayed.
        protected override int GetInitialComponentEditorPageIndex()
        {
            return 1;
        }
    }

    // This example component editor page type provides an example 
    // ComponentEditorPage implementation.
    internal class ExampleComponentEditorPage : System.Windows.Forms.Design.ComponentEditorPage
    {
        Label l1;
        Button b1;
        PropertyGrid pg1;

        public ExampleComponentEditorPage()
        {
            // Initialize the page, which inherits from Panel, and its controls.
            this.Size = new Size(400, 250);
            this.Icon = new Icon("myicon.ico");
            this.Text = "Example Page";

            b1 = new Button();
            b1.Size = new Size(200, 20);
            b1.Location = new Point(200, 0);
            b1.Text = "Set a random background color";
            b1.Click += new EventHandler(this.randomBackColor);
            this.Controls.Add(b1);

            l1 = new Label();
            l1.Size = new Size(190, 20);
            l1.Location = new Point(4, 2);
            l1.Text = "Example Component Editor Page";
            this.Controls.Add(l1);

            pg1 = new PropertyGrid();
            pg1.Size = new Size(400, 280);
            pg1.Location = new Point(0, 30);
            this.Controls.Add(pg1);
        }

        // This method indicates that the Help button should be enabled for this 
        // component editor page.
        public override bool SupportsHelp()
        {
            return true;
        }

        // This method is called when the Help button for this component editor page is pressed.
        // This implementation uses the IHelpService to show the Help topic for a sample keyword.
        public override void ShowHelp()
        {
            // The GetSelectedComponent method of a ComponentEditorPage retrieves the
            // IComponent associated with the WindowsFormsComponentEditor.
            IComponent selectedComponent = this.GetSelectedComponent();

            // Retrieve the Site of the component, and return if null.
            ISite componentSite = selectedComponent.Site;
            if (componentSite == null)
                return;

            // Acquire the IHelpService to display a help topic using a indexed keyword lookup.
            IHelpService helpService = (IHelpService)componentSite.GetService(typeof(IHelpService));
            if (helpService != null)
                helpService.ShowHelpFromKeyword("System.Windows.Forms.ComboBox");
        }

        // The LoadComponent method is raised when the ComponentEditorPage is displayed.
        protected override void LoadComponent()
        {
            this.pg1.SelectedObject = this.Component;
        }

        // The SaveComponent method is raised when the WindowsFormsComponentEditor is closing 
        // or the current ComponentEditorPage is closing.
        protected override void SaveComponent()
        {
        }

        // If the associated component is a Control, this method sets the BackColor to a random color.
        // This method is invoked by the button on this ComponentEditorPage.
        private void randomBackColor(object sender, EventArgs e)
        {
            if (typeof(System.Windows.Forms.Control).IsAssignableFrom(this.Component.GetType()))
            {
                // Sets the background color of the Control associated with the
                // WindowsFormsComponentEditor to a random color.
                Random rnd = new Random();
                ((System.Windows.Forms.Control)this.Component).BackColor =
                    Color.FromArgb(rnd.Next(255), rnd.Next(255), rnd.Next(255));
                pg1.Refresh();
            }
        }
    }

    // This example control is associated with the ExampleComponentEditor 
    // through the following EditorAttribute.
    [EditorAttribute(typeof(ExampleComponentEditor), typeof(ComponentEditor))]
    public class ExampleUserControl : System.Windows.Forms.UserControl
    {
    }
}

注解

组件编辑器用于将组件作为一个整体进行编辑，并可用于实现类似于属性页的用户界面。 使用 EditorAttribute 属性将组件编辑器与组件相关联。

实施者说明

从此类继承时，必须重写 EditComponent(Object) 方法。

构造函数

ComponentEditor()

初始化 ComponentEditor 类的新实例。

方法

EditComponent(ITypeDescriptorContext, Object)	编辑组件并返回一个值，用以指示是否已根据给定上下文修改了组件。
EditComponent(Object)	编辑该组件并返回一个表示是否修改了该组件的值。
Equals(Object)	确定指定对象是否等于当前对象。 (继承自 Object)
GetHashCode()	作为默认哈希函数。 (继承自 Object)
GetType()	获取当前实例的 Type。 (继承自 Object)
MemberwiseClone()	创建当前 Object 的浅表副本。 (继承自 Object)
ToString()	返回表示当前对象的字符串。 (继承自 Object)