顯示只有一些枚舉選項

Question

我已經在PropertyGrid所示的枚舉：

private My_Enum _ee; 

public My_Enum EE 
{ 
    get { return _ee; } 
    set 
    { 
     _ee= value; 
    } 
} 

public enum My_Enum 
{ 
    NUM1 = 0, 
    NUM2 = 1, 
    NUM3 = 2, 
    NUM4 = 3, 
    NUM5 = 4, 
    NUM6 = 5, 
    NUM7 = 6, 
    DEF 
}; 

有沒有辦法在PropertyGrid只有兩個選項，以顯示從枚舉（例如NUM1，NUM2）？

Answer 1

檢查下面的鏈接，你需要使用TypeConverter

• Using PropertyGrid in .NET

• C# Propertygrid combobox with enum values (Win Forms)

Answer 2

您可以定義用來標記字段作爲特殊的屬性，然後，使用自定義UITypeEditor，如下所示：

[Editor(typeof(MyEnumEditor), typeof(UITypeEditor))] 
public enum My_Enum 
{ 
    NUM1 = 0, 
    NUM2 = 1, 
    NUM3 = 2, 
    [Browsable(false)] 
    NUM4 = 3, 
    NUM5 = 4, 
    NUM6 = 5, 
    NUM7 = 6, 
    DEF 
} 

public class MyEnumEditor : UITypeEditor 
{ 
    private IWindowsFormsEditorService _editorService; 
    private bool _cancel; 

    public override UITypeEditorEditStyle GetEditStyle(ITypeDescriptorContext context) 
    { 
     return UITypeEditorEditStyle.DropDown; 
    } 

    public override object EditValue(ITypeDescriptorContext context, IServiceProvider provider, object value) 
    { 
     _cancel = false; 
     _editorService = (IWindowsFormsEditorService)provider.GetService(typeof(IWindowsFormsEditorService)); 
     ListBox listBox = new ListBox(); 
     listBox.IntegralHeight = true; 
     listBox.SelectionMode = SelectionMode.One; 
     listBox.MouseClick += OnListBoxMouseClick; 
     listBox.KeyDown += OnListBoxKeyDown; 
     listBox.PreviewKeyDown += OnListBoxPreviewKeyDown; 

     Type enumType = value.GetType(); 
     if (!enumType.IsEnum) 
      throw new InvalidOperationException(); 

     foreach (FieldInfo fi in enumType.GetFields(BindingFlags.Public | BindingFlags.Static)) 
     { 
      object[] atts = fi.GetCustomAttributes(typeof(BrowsableAttribute), true); 
      if (atts != null && atts.Length > 0 && !((BrowsableAttribute)atts[0]).Browsable) 
        continue; 

      int index = listBox.Items.Add(fi.Name); 

      if (fi.Name == value.ToString()) 
      { 
       listBox.SetSelected(index, true); 
      } 
     } 

     _editorService.DropDownControl(listBox); 
     if ((_cancel) || (listBox.SelectedIndices.Count == 0)) 
      return value; 

     return Enum.Parse(enumType, (string)listBox.SelectedItem); 
    } 

    private void OnListBoxPreviewKeyDown(object sender, PreviewKeyDownEventArgs e) 
    { 
     if (e.KeyCode == Keys.Escape) 
     { 
      _cancel = true; 
      _editorService.CloseDropDown(); 
     } 
    } 

    private void OnListBoxMouseClick(object sender, MouseEventArgs e) 
    { 
     int index = ((ListBox)sender).IndexFromPoint(e.Location); 
     if (index >= 0) 
     { 
      _editorService.CloseDropDown(); 
     } 
    } 

    private void OnListBoxKeyDown(object sender, KeyEventArgs e) 
    { 
     if (e.KeyCode == Keys.Enter) 
     { 
      _editorService.CloseDropDown(); 
     } 
    } 
} 

注意：這不支持標記爲Flags attribute的枚舉，這需要複選框列表。如果你需要的話，它會更復雜，我建議你看看這個免費的庫：CodeFluentRuntimeClient，它在CodeFluent.Runtime.Design命名空間中包含一個支持這個的EnumEditor UITypeEditor類。