IMEX.mes.wcf/DK.Basics/BaseControls/UserControls/DKCheckBoxComboBox/Selection Wrappers/ObjectSelectionWrapper.cs

/*******************************************************************************
 * Copyright(c) 2014 DongkeSoft All rights reserved. / Confidential
 * 类的信息：
 *      1.程序名称：ObjectSelectionWrapper.cs
 *      2.功能描述：类文件
 * 编辑履历：
 *      作者            日期                版本            修改内容
 *      陈晓野          2014/09/29          1.00            新建
 *******************************************************************************/

using System;
using System.ComponentModel;
using System.Data;
using System.Reflection;

namespace Dongke.IBOSS.PRD.Basics.BaseControls
{
    /// <summary>
    /// Used together with the ListSelectionWrapper in order to wrap data sources for a CheckBoxComboBox.
    /// It helps to ensure you don't add an extra "Selected" property to a class that don't really need or want that information.
    /// </summary>
    public class ObjectSelectionWrapper<TItem, TValue>
    {
        public ObjectSelectionWrapper(TItem item, ListSelectionWrapper<TItem, TValue> container)
            : base()
        {
            _Container = container;
            _Item = item;
        }

        #region PRIVATE PROPERTIES

        /// <summary>
        /// Used as a count indicator for the item. Not necessarily displayed.
        /// </summary>
        private int _Count = 0;
        /// <summary>
        /// Is this item selected.
        /// </summary>
        private bool _Selected = false;
        /// <summary>
        /// A reference to the wrapped item.
        /// </summary>
        private TItem _Item;
        /// <summary>
        /// The containing list for these selections.
        /// </summary>
        private ListSelectionWrapper<TItem, TValue> _Container;

        #endregion

        #region PUBLIC PROPERTIES

        /// <summary>
        /// An indicator of how many items with the specified status is available for the current filter level.
        /// Thaught this would make the app a bit more user-friendly and help not to miss items in Statusses
        /// that are not often used.
        /// </summary>
        public int Count
        {
            get { return _Count; }
            set { _Count = value; }
        }
        /// <summary>
        /// A reference to the item wrapped.
        /// </summary>
        public TItem Item
        {
            get { return _Item; }
            //set { _Item = value; }
        }
        public TValue Value
        {
            get
            {
                TValue Value = default(TValue);
                if (string.IsNullOrEmpty(_Container.ValueProperty))
                {    //Value = Item.ToString();
                }
                else if (Item is DataRow) // A specific implementation for DataRow
                {
                    var v = ((DataRow)((Object)Item))[_Container.ValueProperty];
                    Value = (v is TValue) ? (TValue)v : Value;
                }
                else
                {
                    bool isFind = false;
                    PropertyDescriptorCollection PDs = TypeDescriptor.GetProperties(Item);
                    foreach (PropertyDescriptor PD in PDs)
                        if (PD.Name.CompareTo(_Container.ValueProperty) == 0)
                        {
                            var v = PD.GetValue(Item);
                            Value = (v is TValue) ? (TValue)v : Value;
                            isFind = true;
                            break;
                        }
                    if (!isFind)
                    {
                        PropertyInfo PI = Item.GetType().GetProperty(_Container.ValueProperty);
                        if (PI == null)
                            throw new Exception(String.Format(
                                      "Property {0} cannot be found on {1}.",
                                      _Container.DisplayNameProperty,
                                      Item.GetType()));
                        var v = PI.GetValue(Item, null);
                        Value = (v is TValue) ? (TValue)v : Value;
                    }
                }
                return Value;
            }
        }
        /// <summary>
        /// The item display value. If ShowCount is true, it displays the "Name [Count]".
        /// </summary>
        public string Name
        {
            get 
            {
                string Name = null;
                if (string.IsNullOrEmpty(_Container.DisplayNameProperty))
                    Name = Item.ToString();
                else if (Item is DataRow) // A specific implementation for DataRow
                    Name = ((DataRow)((Object)Item))[_Container.DisplayNameProperty].ToString();
                else
                {
                    bool isFind = false;
                    PropertyDescriptorCollection PDs = TypeDescriptor.GetProperties(Item);
                    foreach (PropertyDescriptor PD in PDs)
                        if (PD.Name.CompareTo(_Container.DisplayNameProperty) == 0)
                        {
                            Name = (string)PD.GetValue(Item).ToString();
                            isFind = true;
                            break;
                        }
                    if (!isFind)
                    {
                        PropertyInfo PI = Item.GetType().GetProperty(_Container.DisplayNameProperty);
                        if (PI == null)
                            throw new Exception(String.Format(
                                      "Property {0} cannot be found on {1}.",
                                      _Container.DisplayNameProperty,
                                      Item.GetType()));
                        Name = PI.GetValue(Item, null).ToString();
                    }
                }
                return _Container.ShowCounts ? String.Format("{0} [{1}]", Name, Count) : Name;
            }
        }
        /// <summary>
        /// The textbox display value. The names concatenated.
        /// </summary>
        public string NameConcatenated
        {
            get { return _Container.SelectedNames; }
        }
        public TValue[] ValueConcatenated
        {
            get
            {
                return _Container.SelectedValues;
            }
        }
        /// <summary>
        /// Indicates whether the item is selected.
        /// </summary>
        public bool Selected
        {
            get { return _Selected; }
            set { _Selected = value; }
        }

        #endregion
    }
}