Simplest way to edit a collection in DesignMode?

问题

What is the easiest way to edit and persist a collection like decimal[] or List<string> in the WinForms designer?

The first problem is that a parameterless constructor is needed. So I made a simple wrapper class: (at some point this was like MyObject<T>, but the WinForms designercode generator didn't know how to handle it)

[Serializable()]
public class MyObject
{
      public MyObject() {}
      public decimal Value {get; set;}
}

In the container class we define a property and add the CollectionEditor attribute to it:

public class MyContainer
{
      private List<MyObject> _col = new List<MyObject>();

      [Editor(typeof(CollectionEditor), typeof(System.Drawing.Design.UITypeEditor))]
      public List<MyObject> Collection
      {
           get { return _col; }
           set { _col = value; }
      }
}

Now I tried all sorts of things based on answers here on stackoverflow and articless on codeproject.com:

ArrayEditor with decimal[] field
Custom TypeConverter for MyObject
Custom Collection class for List
Read/Write property on the container class
Custom Editor with implementation for EditValue
Implement IComponent interface for MyObject
Tried adding DesignerSerializationVisibility(DesignerSerializationVisibility.Content)

I did get it to work so that

The collection is visible in DesignMode
The collection is editable in DesignMode
New items can be added to the collection in DesignMode

However, by saving, closing and re-opening the form the elements in the collection are never persisted.

Edit: Hans gave me some tips (his comments somehow went into the void). I followed his guidelines and updated the source above, which unfortunately still doesn't work...

回答1:

I recommend that if possible you expose a colletion property that is the same type as one already used in the framework and so you can reuse the existing collection editor. For example, if you use a StringCollection class then you can do the following and reuse the WinForms existing editor...

    [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
    [Editor("System.Windows.Forms.Design.StringCollectionEditor, 
             System.Design, Version=2.0.0.0, Culture=neutral, 
             PublicKeyToken=b03f5f7f11d50a3a", typeof(UITypeEditor))]
    public StringCollection Items
    {
        get { return _myStringCollection; }
    }

Alternatively if you can expose a string[] then do this...

    [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
    [Editor("System.Windows.Forms.Design.StringArrayEditor, 
            System.Design, Version=2.0.0.0, Culture=neutral, 
            PublicKeyToken=b03f5f7f11d50a3a", typeof(UITypeEditor))]
    public string[] Lines
    {
        get { return _myStringArray; }
        set { myStringArray = value; }
    }

回答2:

Example with List of Objects property:

public partial class SCon : UserControl
{
    public SCon()
    {
        InitializeComponent();
        if (Persoanas == null)
        {
            Persoanas = new List<Persoana>();
        }
    }

    [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
    public List<Persoan> Persoanas { get; set; }

}

[Serializable]
public class Persoan   
{
    public int Id { get; set; }
    public String Name { get; set; }
}

来源：https://stackoverflow.com/questions/6493021/simplest-way-to-edit-a-collection-in-designmode

标签

.net

vb.net

winforms

designmode