Valery

Posted 03 Jan 2018 Link to this post

Dess | Tech Support Engineer, Sr.

Posted 03 Jan 2018 Link to this post

Hello, Valery, 

Thank you for writing.  

The DefaultValueAttribute defines the default value to which the property will be reset. When the property value is set to something different that the default value, it will be marked as modified. Here is a sample code snippet demonstrating how to use the default value: 

public RadForm1()

{

    InitializeComponent();

 

    this.radPropertyGrid1.SelectedObject = new Item();

}

 

public class Item

{

    [DefaultValue(5)]

    public int Id { get; set; }

 

    [DefaultValue("Test")]

    public string Name { get; set; }

 

    [DefaultValue(typeof(Color), "Red")]

    public Color BackColor { get; set; }

 

    public Item()

    {

        this.Id = 5;

        this.Name = "Empty";

        this.BackColor = Color.Red;

    }

}

I hope this information helps. Should you have further questions I would be glad to help.
 
Regards,
Dess
Progress Telerik

Try our brand new, jQuery-free Angular components built from ground-up which deliver the business app essential building blocks - a grid component, data visualization (charts) and form elements.

Valery

Posted 03 Jan 2018 in reply to Dess | Tech Support Engineer, Sr. Link to this post

• Color.png

Dess | Tech Support Engineer, Sr.

Posted 03 Jan 2018 Link to this post

Valery

Posted 03 Jan 2018 in reply to Dess | Tech Support Engineer, Sr. Link to this post

Valery

Posted 03 Jan 2018 in reply to Valery Link to this post

Dess | Tech Support Engineer, Sr.

Posted 04 Jan 2018 Link to this post

Hello, Valery, 

Thank you for writing back. 

Note that the metadata in DefaultValueAttribute is retrieved when it is first requested and it is cached for subsequent retrieval. In order to change the attribute value for a specific property at runtime, you can directly modify the property descriptor for the given property. Here is a code snippet demonstrating this: 

AttributeCollection attributes = TypeDescriptor.GetProperties(this.radPropertyGrid1.SelectedObject)["HiColor"].Attributes;

DefaultValueAttribute myAttribute = (DefaultValueAttribute)attributes[typeof(DefaultValueAttribute)];

FieldInfo defaultValueField = (typeof(DefaultValueAttribute)).GetField("value", BindingFlags.Instance | BindingFlags.NonPublic);

defaultValueField.SetValue(myAttribute, Color.Fuchsia);

RadPropertyGrid offers to reset a property to its default value by using the default context menu: 



I hope this information helps. If you have any additional questions, please let me know. 

 Regards,
Dess
Progress Telerik

Try our brand new, jQuery-free Angular components built from ground-up which deliver the business app essential building blocks - a grid component, data visualization (charts) and form elements.

Valery

Posted 04 Jan 2018 in reply to Dess | Tech Support Engineer, Sr. Link to this post

Dess | Tech Support Engineer, Sr.

Posted 04 Jan 2018 Link to this post