/// <summary>
        /// Log on to a mailbox with a specified user account and create a search folder.
        /// </summary>
        /// <param name="userName">Name of the user.</param>
        /// <param name="userPassword">Password of the user.</param>
        /// <param name="userDomain">Domain of the user.</param>
        /// <param name="searchFolderName">Name of the search folder.</param>
        /// <param name="searchText">Search text of the search folder.</param>
        /// <returns>If the search folder is created successfully, return true; otherwise, return false.</returns>
        public bool CreateSearchFolder(string userName, string userPassword, string userDomain, string searchFolderName, string searchText)
        {
            // Log on mailbox with specified user account(userName, userPassword, userDomain).
            bool isLoged = AdapterHelper.SwitchUser(userName, userPassword, userDomain, this.exchangeServiceBinding, this.Site);
            Site.Assert.IsTrue(
                isLoged,
                string.Format("Log on mailbox with the UserName: {0}, Password: {1}, Domain: {2} should be successful.", userName, userPassword, userDomain));

            // Create the request.
            CreateFolderType createFolder = new CreateFolderType();
            SearchFolderType[] folderArray = new SearchFolderType[1];
            SearchFolderType searchFolder = new SearchFolderType();

            // Use the following search filter to get all mail in the Inbox with the word searchText in the subject line.
            searchFolder.SearchParameters = new SearchParametersType();
            searchFolder.SearchParameters.Traversal = SearchFolderTraversalType.Deep;
            searchFolder.SearchParameters.TraversalSpecified = true;
            searchFolder.SearchParameters.BaseFolderIds = new DistinguishedFolderIdType[4];

            // Create a distinguished folder Identified of the inbox folder.
            DistinguishedFolderIdType inboxFolder = new DistinguishedFolderIdType();
            inboxFolder.Id = new DistinguishedFolderIdNameType();
            inboxFolder.Id = DistinguishedFolderIdNameType.inbox;
            searchFolder.SearchParameters.BaseFolderIds[0] = inboxFolder;
            DistinguishedFolderIdType contactType = new DistinguishedFolderIdType();
            contactType.Id = new DistinguishedFolderIdNameType();
            contactType.Id = DistinguishedFolderIdNameType.contacts;
            searchFolder.SearchParameters.BaseFolderIds[1] = contactType;
            DistinguishedFolderIdType calendarType = new DistinguishedFolderIdType();
            calendarType.Id = new DistinguishedFolderIdNameType();
            calendarType.Id = DistinguishedFolderIdNameType.calendar;
            searchFolder.SearchParameters.BaseFolderIds[2] = calendarType;
            DistinguishedFolderIdType taskType = new DistinguishedFolderIdType();
            taskType.Id = new DistinguishedFolderIdNameType();
            taskType.Id = DistinguishedFolderIdNameType.calendar;
            searchFolder.SearchParameters.BaseFolderIds[3] = taskType;

            // Use the following search filter.
            searchFolder.SearchParameters.Restriction = new RestrictionType();
            PathToUnindexedFieldType path = new PathToUnindexedFieldType();
            path.FieldURI = UnindexedFieldURIType.itemSubject;
            RestrictionType restriction = new RestrictionType();
            FieldURIOrConstantType fieldURIORConstant = new FieldURIOrConstantType();
            fieldURIORConstant.Item = new ConstantValueType();
            (fieldURIORConstant.Item as ConstantValueType).Value = searchText;
            ExistsType isEqual = new ExistsType();
            isEqual.Item = path;
            restriction.Item = isEqual;
            searchFolder.SearchParameters.Restriction = restriction;

            // Give the search folder a unique name.
            searchFolder.DisplayName = searchFolderName;
            folderArray[0] = searchFolder;

            // Create the search folder under the default Search Folder.
            TargetFolderIdType targetFolder = new TargetFolderIdType();
            DistinguishedFolderIdType searchFolders = new DistinguishedFolderIdType();
            searchFolders.Id = DistinguishedFolderIdNameType.searchfolders;
            targetFolder.Item = searchFolders;
            createFolder.ParentFolderId = targetFolder;
            createFolder.Folders = folderArray;
            bool isSearchFolderCreated = false;

            // Invoke CreateFolder operation and get the response.
            CreateFolderResponseType response = this.exchangeServiceBinding.CreateFolder(createFolder);
            if (response != null && ResponseClassType.Success == response.ResponseMessages.Items[0].ResponseClass)
            {
                // If the search folder is created successfully, return true; otherwise, return false.
                isSearchFolderCreated = true;

                searchFolder.FolderId = ((FolderInfoResponseMessageType)response.ResponseMessages.Items[0]).Folders[0].FolderId;
                AdapterHelper.CreatedFolders.Add(searchFolder);
            }

            return isSearchFolderCreated;
        }