MTP2.0_CSharp/Muchinfo.Common/Fx4.0/Muchinfo.DataPager/Base/MuchinfoPagerCommands.cs

/**
    *
    * @date 2014-10-24        
    *
    * @author 邓尹平
    *
    * @par 成员列表类 说明
    * 主要负责管理成员 提供搜索\排序和操作的方法
    * 
    * @par 版权声明
    * 深圳市多元世纪信息技术有限公司 版权所有
    * 
    * @see 使用此类时参照一些其他类可以写在这里
    * 
    * @todo 该类有待完成的任务 一条条列出 完成一条删除一条
    *
    * @bug 该类已知的Bug一条条列出 完成一条删除一条
    *
*/

using System;
using System.Windows.Input;

namespace Muchinfo.DataPager.Base
{
    public class MuchinfoPagerCommands
    {
        private enum CommandId
        {
            MoveToFirstPage,
            MoveToLastPage,
            MoveToNextPage,
            MoveToPage,
            MoveToPreviousPage
        }

        #region Fields

        private static readonly int CommandsCount = Enum.GetNames(typeof(MuchinfoPagerCommands.CommandId)).Length;
        private static readonly RoutedUICommand[] InternalCommands = new RoutedUICommand[MuchinfoPagerCommands.CommandsCount];

        #endregion

        #region Commands

        public static ICommand MoveToFirstPage
        {
            get
            {
                return MuchinfoPagerCommands.EnsureCommand(MuchinfoPagerCommands.CommandId.MoveToFirstPage);
            }
        }
        public static ICommand MoveToLastPage
        {
            get
            {
                return MuchinfoPagerCommands.EnsureCommand(MuchinfoPagerCommands.CommandId.MoveToLastPage);
            }
        }
        public static ICommand MoveToNextPage
        {
            get
            {
                return MuchinfoPagerCommands.EnsureCommand(MuchinfoPagerCommands.CommandId.MoveToNextPage);
            }
        }
        public static ICommand MoveToPage
        {
            get
            {
                return MuchinfoPagerCommands.EnsureCommand(MuchinfoPagerCommands.CommandId.MoveToPage);
            }
        }

        public static ICommand MoveToPreviousPage
        {
            get
            {
                return MuchinfoPagerCommands.EnsureCommand(MuchinfoPagerCommands.CommandId.MoveToPreviousPage);
            }
        }

        #endregion

        #region Methods

        private static RoutedUICommand EnsureCommand(CommandId commandId)
        {
            lock (MuchinfoPagerCommands.InternalCommands.SyncRoot)
            {
                if (MuchinfoPagerCommands.InternalCommands[(int)commandId] == null)
                {
                    var command = new RoutedUICommand(MuchinfoPagerCommands.GetUIText(commandId), commandId.ToString(), typeof(MuchinfoPagerCommands));
                    MuchinfoPagerCommands.InternalCommands[(int)commandId] = command;
                }
            }
            return MuchinfoPagerCommands.InternalCommands[(int)commandId];
        }

        private static string GetUIText(CommandId commandId)
        {
            switch (commandId)
            {
                case MuchinfoPagerCommands.CommandId.MoveToFirstPage:
                    return "Move to first page";
                case MuchinfoPagerCommands.CommandId.MoveToLastPage:
                    return "Move to last page";
                case MuchinfoPagerCommands.CommandId.MoveToNextPage:
                    return "Move to next page";
                case MuchinfoPagerCommands.CommandId.MoveToPage:
                    return "Move to page";
                case MuchinfoPagerCommands.CommandId.MoveToPreviousPage:
                    return "Move to previous page";
                default:
                    return string.Empty;
            }
        }

        #endregion
    }
}