How to modify PropertyGrid at runtime (add/remove property and dynamic types/enums)

Question

How do you modify a propertygrid at runtime in every way? I want to be able to add and remove properties and add \"dynamic types\", what I mean with that is a type that resu

Answer 1

in my case TypeConverter did not apply to States class

[TypeConverter(typeof(StatesList))] // not work
public class States
{
}

so i added override in CustomPropertyDescriptor

public override TypeConverter Converter
{
    get {
        if (this.PropertyType.Equals(typeof(States)) ) {
            return new StatesList(); ; 
        }
        return base.Converter;
    }
}

Answer 2

This question and answer was of great usefulness to me. However, I needed to extend things a bit further by allowing for run-time generated dropdown list values. I thought I would post some sample code in regards to what it required, in case anyone finds it useful.

First, I added an options parameter to the CustomProperty constructor and added an Options property:

    private List<string> lOptions;

    public CustomProperty(string sName, object value, Type tType, bool bReadOnly, bool bVisible, List<string> lOptions)
    {
        this.lOptions = lOptions;
    }

    public List<string> Options
    {
        get { return lOptions; }
    }

Second, I added an Options property to the CustomPropertyDescriptor class:

    public List<string> Options
    {
        get
        {
            return m_Property.Options;
        }
    }

Third, I had to modify the GetStandardValues method in my dynamic type class (i.e. StatesList) to make use of the new Options property on the CustomPropertyDescriptor Object:

    public override StandardValuesCollection
                 GetStandardValues(ITypeDescriptorContext context)
    {
        CustomPropertyDescriptor descriptor = (CustomPropertyDescriptor)context.PropertyDescriptor;
        return new StandardValuesCollection(descriptor.Options);
    }

Finally, I had to pass in my list of options when creating a new CustomProperty object:

    List<string> optionsList = new List<string>(new string[] { "test1", "test2", "test3" });        
    CustomProperty myProperty = new CustomProperty(attr.Name, attr.Value, valueType, false, true, optionsList);

In place of the static list that I passed in for this example, you can generate the list of options for your dropdown in any manner that you please, giving you full control over the options available.

Answer 3

What you do, is adding StatesList (a TypeConverter) as a property.
What you should do, is adding a property with StatesList as its TypeConverter.

Answer 4

Ah, of course!

myProperties.Add(new CustomProperty("Custom", "", typeof(States), false, true));

[TypeConverter(typeof(StatesList))]
public class States
{
}

Works like a charm, thank you!

I have updated my project, hope it can be helpful to others, it can be found here.