XCeed PropertyGrid：如何添加bool（CheckBox）类型的自定义PropertyDefinition属性

你的代码问题出在HasAttribute的错误用法——这个属性是用来筛选带有指定特性的现有属性，不是用来定义属性类型的。以下分两种场景给出解决方案：

场景1：目标对象可以直接添加属性（推荐） #

如果PropertyGrid绑定的对象（SelectedObject）是你可控的类，直接在类里定义KeepRatio属性即可，PropertyGrid会自动识别bool类型并显示为CheckBox：

// 你的目标类
public class LayoutSettings
{
    [Category("Layout")] // 指定分类
    [DisplayName("KeepRatio")] // 显示名称
    public bool KeepRatio { get; set; } = false; // 默认值
}

// 绑定到PropertyGrid
propertyGrid1.SelectedObject = new LayoutSettings();

如果是用Telerik的PropertyGrid（你的代码里用到了PropertyDefinitions），也可以手动添加定义（但其实控件会自动识别属性，手动添加是为了自定义显示逻辑）：

var propertyDefinition = new PropertyDefinition()
{
    Category = "Layout",
    DisplayName = "KeepRatio",
    TargetProperties = new string[] { "KeepRatio" }
    // 无需设置HasAttribute，控件会根据属性类型自动使用CheckBox编辑器
};

propertyGrid1.PropertyDefinitions.Add(propertyDefinition);

场景2：无法修改目标对象，动态添加属性 #

如果绑定的对象是第三方类，无法直接添加属性，可以通过自定义TypeDescriptor动态注入属性：

1. 实现自定义类型描述器相关类 #

using System.ComponentModel;

public class CustomTypeProvider : TypeDescriptionProvider
{
    private readonly TypeDescriptionProvider _baseProvider;

    public CustomTypeProvider(TypeDescriptionProvider baseProvider)
    {
        _baseProvider = baseProvider;
    }

    public override ICustomTypeDescriptor GetTypeDescriptor(Type objectType, object instance)
    {
        var baseDescriptor = _baseProvider.GetTypeDescriptor(objectType, instance);
        return new CustomPropertyDescriptorWrapper(baseDescriptor);
    }
}

public class CustomPropertyDescriptorWrapper : CustomTypeDescriptor
{
    public CustomPropertyDescriptorWrapper(ICustomTypeDescriptor parent) : base(parent) { }

    public override PropertyDescriptorCollection GetProperties(Attribute[] attributes)
    {
        var originalProps = base.GetProperties(attributes);
        var customProps = new List<PropertyDescriptor>();

        // 添加自定义的KeepRatio属性
        var keepRatioProp = new DynamicBoolProperty(
            "KeepRatio",
            new CategoryAttribute("Layout"),
            new DisplayNameAttribute("KeepRatio")
        );

        customProps.AddRange(originalProps.Cast<PropertyDescriptor>());
        customProps.Add(keepRatioProp);

        return new PropertyDescriptorCollection(customProps.ToArray());
    }
}

public class DynamicBoolProperty : PropertyDescriptor
{
    private bool _currentValue;

    public DynamicBoolProperty(string name, params Attribute[] attrs) : base(name, attrs)
    {
        _currentValue = false;
    }

    public override bool CanResetValue(object component) => true;
    public override object GetValue(object component) => _currentValue;
    public override void ResetValue(object component) => _currentValue = false;
    public override void SetValue(object component, object value) => _currentValue = (bool)value;
    public override bool ShouldSerializeValue(object component) => true;
    public override Type ComponentType => typeof(object);
    public override bool IsReadOnly => false;
    public override Type PropertyType => typeof(bool);
}

2. 应用到目标对象并绑定 #

// 假设你的原始对象是thirdPartyObject
var provider = new CustomTypeProvider(TypeDescriptor.GetProvider(thirdPartyObject));
TypeDescriptor.AddProvider(provider, thirdPartyObject);

propertyGrid1.SelectedObject = thirdPartyObject;

这样PropertyGrid就会显示动态添加的KeepRatio复选框属性。

内容的提问来源于stack exchange，提问作者Muhammad Salman