在属性网格中使用字典

Question

我想使用属性网格编辑一个键值对(string, string)列表。当我使用Dictionary<string,string>类型时，属性网格会显示一个GUI界面，但它似乎是“禁用”的，即我无法添加任何项目。

字典对象是否被支持？或者是否有其他对象可解决此问题？

- Robert Massa

Answer 1

我曾经按照这篇文章中的代码进行过操作：

class DictionaryPropertyGridAdapter : ICustomTypeDescriptor
{
    IDictionary _dictionary;

    public DictionaryPropertyGridAdapter(IDictionary d)
    {
        _dictionary = d;
    }

    public string GetComponentName()
    {
        return TypeDescriptor.GetComponentName(this, true);
    }

    public EventDescriptor GetDefaultEvent()
    {
        return TypeDescriptor.GetDefaultEvent(this, true);
    }

    public string GetClassName()
    {
        return TypeDescriptor.GetClassName(this, true);
    }

    public EventDescriptorCollection GetEvents(Attribute[] attributes)
    {
        return TypeDescriptor.GetEvents(this, attributes, true);
    }

    EventDescriptorCollection System.ComponentModel.ICustomTypeDescriptor.GetEvents()
    {
        return TypeDescriptor.GetEvents(this, true);
    }

    public TypeConverter GetConverter()
    {
        return TypeDescriptor.GetConverter(this, true);
    }

    public object GetPropertyOwner(PropertyDescriptor pd)
    {
        return _dictionary;
    }

    public AttributeCollection GetAttributes()
    {
        return TypeDescriptor.GetAttributes(this, true);
    }

    public object GetEditor(Type editorBaseType)
    {
        return TypeDescriptor.GetEditor(this, editorBaseType, true);
    }

    public PropertyDescriptor GetDefaultProperty()
    {
        return null;
    }

    PropertyDescriptorCollection
        System.ComponentModel.ICustomTypeDescriptor.GetProperties()
    {
        return ((ICustomTypeDescriptor)this).GetProperties(new Attribute[0]);
    }

    public PropertyDescriptorCollection GetProperties(Attribute[] attributes)
    {
        ArrayList properties = new ArrayList();
        foreach (DictionaryEntry e in _dictionary)
        {
            properties.Add(new DictionaryPropertyDescriptor(_dictionary, e.Key));
        }

        PropertyDescriptor[] props =
            (PropertyDescriptor[])properties.ToArray(typeof(PropertyDescriptor));

        return new PropertyDescriptorCollection(props);
    }
}

class DictionaryPropertyDescriptor : PropertyDescriptor
{
    IDictionary _dictionary;
    object _key;

    internal DictionaryPropertyDescriptor(IDictionary d, object key)
        : base(key.ToString(), null)
    {
        _dictionary = d;
        _key = key;
    }

    public override Type PropertyType
    {
        get { return _dictionary[_key].GetType(); }
    }

    public override void SetValue(object component, object value)
    {
        _dictionary[_key] = value;
    }

    public override object GetValue(object component)
    {
        return _dictionary[_key];
    }

    public override bool IsReadOnly
    {
        get { return false; }
    }

    public override Type ComponentType
    {
        get { return null; }
    }

    public override bool CanResetValue(object component)
    {
        return false;
    }

    public override void ResetValue(object component)
    {
    }

    public override bool ShouldSerializeValue(object component)
    {
        return false;
    }
}

private void Form1_Load(object sender, System.EventArgs e)
{
    IDictionary d = new Hashtable();
    d["Hello"] = "World";
    d["Meaning"] = 42;
    d["Shade"] = Color.ForestGreen;

    propertyGrid1.SelectedObject = new DictionaryPropertyGridAdapter(d);
}

对我们很有帮助。

- Iain

---

更新博客文章链接：http://blog.differentpla.net/blog/2005/02/26/using-propertygrid-with-a-dictionary-object - Mikhail

Answer 2

如果您想将一个包含字典属性的类绑定到PropertyGrid，而不是直接绑定该字典本身，那么这里有一个免费（LGPL许可证）的组件可以实现这一点：http://gendictedit.codeplex.com/

- PolyTekPatrick