AipGateway/Experimental.System.Messaging-master/Experimental.System.Messaging/Messaging/Design/MessageQueueConverter.cs

//------------------------------------------------------------------------------
// <copyright file="MessageQueueConverter.cs" company="Microsoft">
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// </copyright>                                                                
//------------------------------------------------------------------------------

using Experimental.System.Messaging;
using System;
using System.Collections;
using System.ComponentModel;
using System.Globalization;

namespace Experimental.System.Messaging.Design
{
    /// <include file='doc\MessageQueueConverter.uex' path='docs/doc[@for="MessageQueueConverter"]/*' />
    /// <internalonly/>
    internal class MessageQueueConverter : TypeConverter
    {
        private static Hashtable componentsCreated = new Hashtable(StringComparer.InvariantCultureIgnoreCase);

        /// <include file='doc\MessageQueueConverter.uex' path='docs/doc[@for="MessageQueueConverter.CanConvertFrom"]/*' />
        /// <internalonly/>                               
        public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
        {
            if (sourceType == typeof(string))
            {
                return true;
            }
            return base.CanConvertFrom(context, sourceType);
        }

        internal static void AddToCache(MessageQueue queue)
        {
            componentsCreated[queue.Path] = queue;
        }

        /// <include file='doc\MessageQueueConverter.uex' path='docs/doc[@for="MessageQueueConverter.ConvertFrom"]/*' />
        /// <internalonly/>                 
        public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
        {
            if (value != null && value is string)
            {
                string text = ((string)value).Trim();

                if (text == String.Empty)
                    return null;

                if (text.CompareTo(Res.GetString(Res.NotSet)) != 0)
                {
                    MessageQueue newQueue = GetFromCache(text);
                    if (newQueue != null)
                        return newQueue;
                    else
                    {
                        newQueue = new MessageQueue(text);
                        AddToCache(newQueue);
                        if (context != null)
                            context.Container.Add(newQueue);

                        return newQueue;
                    }
                }
            }

            return null;
        }


        /// <include file='doc\MessageQueueConverter.uex' path='docs/doc[@for="MessageQueueConverter.ConvertTo"]/*' />
        /// <internalonly/>                 
        public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType)
        {
            if (destinationType != null && destinationType == typeof(string))
            {
                if (value != null)
                    return ((MessageQueue)value).Path;
                else
                    return Res.GetString(Res.NotSet);
            }

            return base.ConvertTo(context, culture, value, destinationType);
        }

        internal static MessageQueue GetFromCache(string path)
        {
            if (componentsCreated.ContainsKey(path))
            {
                MessageQueue existingComponent = (MessageQueue)componentsCreated[path];
                if (existingComponent.Site == null)
                    componentsCreated.Remove(path);
                else
                {
                    if (existingComponent.Path == path)
                        return existingComponent;
                    else
                        componentsCreated.Remove(path);
                }
            }

            return null;
        }
    }
}