如何从属性窗口设置 UserControl 的自定义属性，这是一个类

Question

我创建了一个扩展 PictureBox 控件的用户控件

public partial class AudioMonitor : PictureBox
{
    private SelectionSettings _selectionSettings;

    [Description("Various settings regarding to the selection visuals"), Category("Custom")]
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    public SelectionSettings SelectionSettings
    {
        get { return this._selectionSettings; }
        set { this._selectionSettings = value; }
    }
}

SelectionSettings 属性是我创建的自定义类，如下所示：

[Serializable]
public class SelectionSettings
{
    private SelectionMarker _startMarker;
    private SelectionMarker _endMarker;
    private SelectionPen _selectionStyle;

    public SelectionMarker StartMarker
    {
        get { return this._startMarker; }
        set { this._startMarker = value; }
    }
    public SelectionMarker EndMarker
    {
        get { return this._endMarker; }
        set { this._endMarker = value; }
    }
    public SelectionPen SelectionStyle
    {
        get { return this._selectionStyle; }
        set { this._selectionStyle = value; }
    }
}

[Serializable]
public class SelectionMarker
{
    private Color _color = Color.White;
    private DashStyle _style = DashStyle.Solid;
    private float _width = 1.0F;

    public Color Color
    {
        get { return this._color; }
        set { this._color = value; }
    }
    public DashStyle Style
    {
        get { return this._style; }
        set { this._style = value; }
    }
    public float Width
    {
        get { return this._width; }
        set { this._width = value; }
    }
    public Pen Pen
    {
        get
        {
            Pen pen = new Pen(this._color);
            pen.DashStyle = this._style;
            pen.Width = this._width;

            return pen;
        }
    }
}

[Serializable]
public class SelectionPen
{
    private Color _color = Color.White;
    private DashStyle _style = DashStyle.Solid;
    private float _width = 1.0F;
    private float _alpha = 100;

    public Color Color
    {
        get { return this._color; }
        set { this._color = value; }
    }
    public DashStyle Style
    {
        get { return this._style; }
    }
    public float Width
    {
        get { return this._width; }
    }
    public float Alpha
    {
        get { return this._alpha; }
    }
    public int AlphaPercent
    {
        get { return (int)Math.Round(this._alpha * 100 / 255); }
        set
        {
            if (value > 0 && value <= 100)
                this._alpha = (value * 255 / 100);
            else
                throw new ArgumentException("Alpha percentage should be between (0, 100]");
        }
    }
    public Pen Pen
    {
        get
        {
            Pen pen = new Pen(Color.FromArgb((byte)this._alpha, this._color.R, this._color.G, this._color.B));
            pen.DashStyle = this._style;
            pen.Width = this._width;

            return pen;
        }
    }
}

当我将自定义控件放在窗体上并打开属性窗口时，我可以看到如下：

如您所见，我无法在设计时从“属性”窗口设置“SelectionSettings”属性。我需要的是在属性名称旁边放置“...”按钮并打开一个弹出窗口来设置值。

它应该看起来像这样：

我怎样才能完成这项任务？

Answer 1

您要做的是将Editor 添加到AudioMonitor 的SelectionSettings 属性。

为此，您应该创建一个从UITypeEditor Class 派生的自定义类。

为了从UITypeEditor继承，您的项目必须引用System.Design，这可以通过转到项目菜单，选择添加引用以打开引用管理器，导航到左侧的Assemblies->Framework来完成面板并确保在列表中选中System.Design。

在您的自定义UITypeEditor 派生类中，覆盖方法EditValue 以显示一个自定义对话框，该对话框编辑SelectionSettings 类型的值。然后将 SelectionSettings 属性上的 Editor Attribute 设置为自定义的 UITypeEditor 派生类。

下面是一个通用的代码示例：

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

// ...

[Editor(typeof(SomeProperty_Editor), typeof(UITypeEditor))] // You might be able to place this attribute on class SomeType, but I haven't tried yet
public SomeType SomeProperty
{
    get { /* stuff */ }
    set { /* stuff */ } // optional, really
}

class SomeProperty_Editor : UITypeEditor
{
    public override UITypeEditorEditStyle GetEditStyle(ITypeDescriptorContext context)
    {
        return UITypeEditorEditStyle.Modal;
    }

    public override object EditValue(ITypeDescriptorContext context, IServiceProvider provider, object value)
    {
        IWindowsFormsEditorService service = (IWindowsFormsEditorService)(provider.GetService(typeof(IWindowsFormsEditorService)));
        SomeProperty_EditorWindow EditorWindow = new SomeProperty_EditorWindow(value as SomeType);
        service.ShowDialog(EditorWindow);
        if (EditorWindow.EditCancelled)
            return value;
        else
            return EditorWindow.GetEdittedValue();
    }
}

class SomeProperty_EditorWindow : Form
{
    public SomeProperty_EditorWindow(SomeType CurrentProperty) : base()
    {
        InitializeComponents();

        // Grab info in CurrentProperty here and display it on form
    }

    public void InitializeComponents()
    {
        // write yourself or use designer
    }

    public SomeType GetEdittedValue()
    {
        // return editted value from form components 
    }

    public bool EditCancelled = false; // Set true if cancel button hit
}

您可能需要查找PropertyGrid 控件，因为它在您的EditorWindow 中可能非常有用。此外，您可以转到UITypeEditor Class 的 MSDN 页面，查看“继承层次结构”下的所有 .NET 派生类，看看是否有一个内置编辑器，它的功能与您想要做的事情和继承很接近直接来自那个班级。