WPF Drag-and-Drop Smorgasbord

#define PRINT2OUTPUT

using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Controls;
using System.Windows;
using System.Xml;
using System.Diagnostics;
using System.Windows.Input;
using System.Windows.Media;



namespace WpfDragAndDropSmorgasbord.DragDropFramework
{

    /// <summary>
    /// This class provides some default implementations for
    /// IDataConsumer that can be used by derived classes.
    /// This class represents dragged data that can be consumed.
    /// </summary>
    public abstract class DataConsumerBase : IDataConsumer
    {
        /// <summary>
        /// A list of formats this data object consumer supports
        /// </summary>
        private string[] _dataFormats;

        /// <summary>
        /// Create a Data Consumer that supports
        /// the specified data formats
        /// </summary>
        /// <param name="dataFormats">Data formats supported by this data consumer</param>
        public DataConsumerBase(string[] dataFormats) {
            this._dataFormats = dataFormats;
            Debug.Assert((dataFormats != null) && (dataFormats.Length > 0), "Must have at least one format string");
        }

        /// <summary>
        /// Returns the actions supported by this data object consumer
        /// </summary>
        public abstract DataConsumerActions DataConsumerActions {
            get;
            //{
            //    return
            //        DataConsumerActions.DragEnter |
            //        DataConsumerActions.DragOver |
            //        DataConsumerActions.Drop |
            //        DataConsumerActions.DragLeave |

            //        DataConsumerActions.None;
            //}
        }

        /// <summary>
        /// Search the available data formats for a
        /// supported data format and return the first match
        /// </summary>
        /// <param name="e">DragEventArgs from one of the four Drag events</param>
        /// <returns>Returns first available/supported data object match; null when no match is found</returns>
        public virtual object GetData(DragEventArgs e) {
            object data = null;
            string[] dataFormats = e.Data.GetFormats();
            foreach(string dataFormat in dataFormats) {
                foreach(string dataFormatString in this._dataFormats) {
                    if(dataFormat.Equals(dataFormatString)) {
                        try {
                            data = e.Data.GetData(dataFormat);
                        }
                        catch /*(COMException e2)*/ {
                            ;
                        }
                    }
                    if(data != null)
                        return data;
                }
            }

            return null;
        }

        /// <summary>
        /// Occurs when mouse enters the area occupied
        /// by the dropTarget (specified in the constructor).
        /// Provide your own method if you wish; making sure
        /// to define DragEnter in DataConsumerActions.
        /// 
        /// See DropTarget_DragEnter in DropManager for additional comments.
        /// </summary>
        /// <param name="sender">Drag event <code>sender</code></param>
        /// <param name="e">DragEnter event arguments</param>
        public virtual void DropTarget_DragEnter(object sender, DragEventArgs e) {
            throw new NotImplementedException("DragEnter not implemented");
        }

        /// <summary>
        /// Occurs when mouse is over the area occupied
        /// by the dropTarget (specified in the constructor).
        /// You must likely will provide your own method; make sure
        /// to define DragOver in DataConsumerActions.
        /// </summary>
        /// <param name="sender">Drag event <code>sender</code></param>
        /// <param name="e">DragOver event arguments</param>
        public virtual void DropTarget_DragOver(object sender, DragEventArgs e) {
            throw new NotImplementedException("DragOver not implemented");
        }

        /// <summary>
        /// Occurs when the left mouse button is released in the area
        /// occupied by the dropTarget (specified in the constructor).
        /// You must likely will provide your own method; make sure
        /// to define Drop in DataConsumerActions.
        /// 
        /// See DropTarget_DragEnter in DropManager for additional comments.
        /// </summary>
        /// <param name="sender">Drag event <code>sender</code></param>
        /// <param name="e">Drop event arguments</param>
        public virtual void DropTarget_Drop(object sender, DragEventArgs e) {
            throw new NotImplementedException("Drop not implemented");
        }

        /// <summary>
        /// Occurs when mouse leaves the area occupied
        /// by the dropTarget (specified in the constructor).
        /// Provide your own method if you wish; making sure
        /// to define DragEnter in DataConsumerActions.
        /// 
        /// See DropTarget_DragLeave in DropManager for additional comments.
        /// </summary>
        /// <param name="sender">Drag event <code>sender</code></param>
        /// <param name="e">DragLeave event arguments</param>
        public virtual void DropTarget_DragLeave(object sender, DragEventArgs e) {
            throw new NotImplementedException("DragLeave not implemented");
        }
    }
}