概要

using System.Reflection;
using UnityEditor;
using UnityEngine;

public static class Example
{
    [MenuItem( "Tools/Hoge" )]
    private static void Hoge()
    {
        var rectTransform    = ( RectTransform ) Selection.activeTransform;
        var type             = typeof( RectTransform );
        var propertyInfo     = type.GetProperty( "drivenProperties", BindingFlags.Instance | BindingFlags.NonPublic );
        var drivenProperties = propertyInfo.GetValue( rectTransform );

        Debug.Log( drivenProperties );
    }
}