C# EWS-如何在日期之间搜索项目[消息]？

我正在尝试从收件箱文件夹中搜索两个日期之间的邮件项目。 我使用以下restrictionType，但它会引发此错误：

firmt.RootFolder=null

我做错了什么

在提到的日期之间有一些消息；-）

谢谢你的建议

        using (ExchangeServiceBinding esb = new ExchangeServiceBinding())
        {
            esb.Url = ConfigurationManager.AppSettings["ExchangeWebServicesURL"].ToString();
            esb.RequestServerVersionValue = new RequestServerVersion();
            esb.RequestServerVersionValue.Version = ExchangeVersionType.Exchange2007_SP1;
            esb.PreAuthenticate = true;
            esb.Credentials = new NetworkCredential(email, password);
            FindItemType findItemRequest = new FindItemType();
            // paging
            IndexedPageViewType ipvt = new IndexedPageViewType();
            ipvt.BasePoint = IndexBasePointType.Beginning;
            ipvt.MaxEntriesReturned = nombreMessage;
            ipvt.MaxEntriesReturnedSpecified = true;
            ipvt.Offset = offset;
            findItemRequest.Item = ipvt;
            // filter by dates
            AndType andType = new AndType();
            List<SearchExpressionType> searchExps = new List<SearchExpressionType>();
            RestrictionType restriction = new RestrictionType();
            PathToUnindexedFieldType pteft = new PathToUnindexedFieldType
            {
                FieldURI = UnindexedFieldURIType.itemDateTimeSent
            };
            IsGreaterThanOrEqualToType IsGreaterThanOrEqualTo = new IsGreaterThanOrEqualToType
            {
                Item = pteft,
                FieldURIOrConstant = new FieldURIOrConstantType
                {
                    Item = new ConstantValueType
                    {
                        Value = DateTime.Today.AddDays(-6d).ToString()
                    }
                }
            };
            searchExps.Add(IsGreaterThanOrEqualTo);

            IsLessThanOrEqualToType IsLessThanOrEqualTo = new IsLessThanOrEqualToType
            {
                Item = pteft,
                FieldURIOrConstant = new FieldURIOrConstantType
                {
                    Item = new ConstantValueType
                    {
                        Value = DateTime.Today.AddDays(1d).ToString()
                    }
                }
            };
            searchExps.Add(IsLessThanOrEqualTo);
            andType.Items = searchExps.ToArray();
            restriction.Item = andType;
            findItemRequest.Restriction = restriction;
            //// Define the sort order of items.
            FieldOrderType[] fieldsOrder = new FieldOrderType[1];
            fieldsOrder[0] = new FieldOrderType();
            PathToUnindexedFieldType dateOrder = new PathToUnindexedFieldType
            {
                FieldURI = UnindexedFieldURIType.itemDateTimeReceived
            };
            fieldsOrder[0].Item = dateOrder;
            fieldsOrder[0].Order = SortDirectionType.Descending;
            findItemRequest.SortOrder = fieldsOrder;
            findItemRequest.Traversal = ItemQueryTraversalType.Shallow;
            // define which item properties are returned in the response 
            findItemRequest.ItemShape = new ItemResponseShapeType
            {
                BaseShape = DefaultShapeNamesType.IdOnly
            };
            // identify which folder to search 
            DistinguishedFolderIdType[] folderIDArray = new DistinguishedFolderIdType[1];
            folderIDArray[0] = new DistinguishedFolderIdType { Id = DistinguishedFolderIdNameType.inbox };
            // add folders to request 
            findItemRequest.ParentFolderIds = folderIDArray;
            // find the messages 
            FindItemResponseType findItemResponse = esb.FindItem(findItemRequest);
            //-------------
            ArrayOfResponseMessagesType responseMessages = findItemResponse.ResponseMessages;
            ResponseMessageType responseMessage = responseMessages.Items[0];
            if (responseMessage is FindItemResponseMessageType)
            {
                FindItemResponseMessageType firmt = (responseMessage as FindItemResponseMessageType);
         *******FindItemParentType fipt = firmt.RootFolder;********
                object obj = fipt.Item;
                // FindItem contains an array of items.
                ArrayOfRealItemsType realitems = (obj as ArrayOfRealItemsType);
                ItemType[] items = realitems.Items;
                // if no messages were found, then return null -- we're done 
                if (items == null || items.Count() <= 0)
                    return null;
                // FindItem never gets "all" the properties, so now that we've found them all, we need to get them all. 
                BaseItemIdType[] itemIds = new BaseItemIdType[items.Count()];
                for (int i = 0; i < items.Count(); i++)
                    itemIds[i] = items[i].ItemId;
                GetItemType getItemType = new GetItemType
                {
                    ItemIds = itemIds,
                    ItemShape = new ItemResponseShapeType
                    {
                        BaseShape = DefaultShapeNamesType.AllProperties,
                        BodyType = BodyTypeResponseType.Text,
                        BodyTypeSpecified = true,
                        AdditionalProperties = new BasePathToElementType[] { 
                            new PathToUnindexedFieldType { FieldURI = UnindexedFieldURIType.itemDateTimeSent },
                            new PathToUnindexedFieldType { FieldURI = UnindexedFieldURIType.messageFrom },
                            new PathToUnindexedFieldType { FieldURI = UnindexedFieldURIType.messageIsRead },
                            new PathToUnindexedFieldType { FieldURI = UnindexedFieldURIType.messageSender },
                            new PathToUnindexedFieldType { FieldURI = UnindexedFieldURIType.messageToRecipients },
                            new PathToUnindexedFieldType { FieldURI = UnindexedFieldURIType.messageCcRecipients },
                            new PathToUnindexedFieldType { FieldURI = UnindexedFieldURIType.messageBccRecipients }
                        }
                    }
                };
                GetItemResponseType getItemResponse = esb.GetItem(getItemType);
                messages = ReadItems(getItemResponse, items.Count());
            }

使用（ExchangeServiceBinding esb=new ExchangeServiceBinding（））
{
esb.Url=ConfigurationManager.AppSettings[“ExchangeWebServicesURL”].ToString（）；
esb.RequestServerVersionValue=新的RequestServerVersion（）；
esb.RequestServerVersionValue.Version=ExchangeVersionType.Exchange2007_SP1；
esb.PreAuthenticate=true；
esb.Credentials=新的网络凭据（电子邮件、密码）；
FindItemType findItemRequest=新的FindItemType（）；
//寻呼
IndexedPageViewType ipvt=新IndexedPageViewType（）；
ipvt.BasePoint=IndexBasePointType.Start；
ipvt.MaxEntriesReturned=nombreMessage；
ipvt.MaxEntriesReturnedSpecified=true；
偏移量=偏移量；
findItemRequest.Item=ipvt；
//按日期筛选
AndType AndType=新AndType（）；
List searchExps=新列表（）；
RestrictionType restriction=新的RestrictionType（）；
PathToUnindexedFieldType pteft=新的PathToUnindexedFieldType
{
FieldURI=UnindexedFieldURIType.itemDateTimeSent
};
IsGreaterThanOrEqualToType IsGreaterThanOrEqualTo=新IsGreaterThanOrEqualToType
{
项目=pteft，
FieldURIOrConstant=新的FieldURIOrConstantType
{
Item=新的ConstantValue类型
{
Value=DateTime.Today.AddDays（-6d）.ToString（）
}
}
};
searchExps.Add（大于或等于0）；
IsLessThanOrEqualToType IsLessThanOrEqualTo=新IsLessThanOrEqualToType
{
项目=pteft，
FieldURIOrConstant=新的FieldURIOrConstantType
{
Item=新的ConstantValue类型
{
Value=DateTime.Today.AddDays（1d）.ToString（）
}
}
};
searchExps.Add（IsLessThanOrEqualTo）；
andType.Items=searchExps.ToArray（）；
限制。项=和类型；
findItemRequest.Restriction=限制；
////定义项目的排序顺序。
FieldOrderType[]fieldsOrder=新的FieldOrderType[1]；
fieldsOrder[0]=新的FieldOrderType（）；
PathToUnindexedFieldType dateOrder=新的PathToUnindexedFieldType
{
FieldURI=UnindexedFieldURIType.itemDateTimeReceived
};
fieldsOrder[0]。项=日期顺序；
fieldsOrder[0]。顺序=SortDirectionType.Descending；
findItemRequest.SortOrder=字段排序器；
findItemRequest.Traversal=ItemQueryTraversalType.Shallow；
//定义响应中返回的项属性
findItemRequest.ItemShape=新的ItemResponseShapeType
{
BaseShape=DefaultShapeNameType.IdOnly
};
//确定要搜索的文件夹
DifferentiedFolderIDType[]folderIDArray=新的DifferentiedFolderIDType[1]；
folderIDArray[0]=新的DifferentiedFolderIDType{Id=DifferentiedFolderIDNameType.inbox}；
//向请求添加文件夹
findItemRequest.ParentFolderId=FolderDarray；
//查找消息
FindItemResponseType findItemResponse=esb.FindItem（findItemRequest）；
//-------------
ArrayOfResponseMessageType responseMessages=findItemResponse.responseMessages；
ResponseMessageType responseMessage=responseMessages.Items[0]；
if（responseMessage为FindItemResponseMessageType）
{
FindItemResponseMessageType firmt=（响应消息为FindItemResponseMessageType）；
*******FindItemParentType fipt=firmt.RootFolder********
对象对象=初始项；
//FindItem包含一个项目数组。
ArrayOfRealItemsType realitems=（对象为ArrayOfRealItemsType）；
ItemType[]items=realitems.items；
//如果没有找到任何消息，则返回null——我们完成了
如果（items==null | | items.Count（）在对日期格式进行长时间搜索后，我自己找到了答案

这些限制必须定义为：

// greater or equal to 
string dateStart = DateTime.Today.add(-6d);
string dateEnd = DateTime.Today.Add(1d);

PathToUnindexedFieldType dateSentPath = new PathToUnindexedFieldType();
dateSentPath.FieldURI = UnindexedFieldURIType.itemDateTimeSent;
IsGreaterThanOrEqualToType IsGreaterThanOrEqual = new IsGreaterThanOrEqualToType();
IsGreaterThanOrEqual.Item = dateSentPath;
FieldURIOrConstantType dateConstant = new FieldURIOrConstantType();
ConstantValueType dateConstantValue = new ConstantValueType();
dateConstantValue.Value = string.Format("{0}-{1}-{2}T00:00:00Z", dateStart.Year.ToString(), dateStart.Month.ToString(), dateStart.Day.ToString());
dateConstant.Item = dateConstantValue;
IsGreaterThanOrEqual.FieldURIOrConstant = dateConstant;

// less than or equal to
PathToUnindexedFieldType dateSentPath1 = new PathToUnindexedFieldType();
dateSentPath1.FieldURI = UnindexedFieldURIType.itemDateTimeSent;
IsLessThanOrEqualToType lessThanOrEqualTo = new IsLessThanOrEqualToType();
lessThanOrEqualTo.Item = dateSentPath1;
FieldURIOrConstantType dateConstant1 = new FieldURIOrConstantType();
ConstantValueType dateConstantValue1 = new ConstantValueType();
dateConstantValue1.Value = string.Format("{0}-{1}-{2}T00:00:00Z", dateEnd.Year.ToString(), dateEnd.Month.ToString(), dateEnd.Day.ToString());
dateConstant1.Item = dateConstantValue1;
lessThanOrEqualTo.FieldURIOrConstant = dateConstant1;

RestrictionType restriction = new RestrictionType();
AndType andType = new AndType();
andType.Items = new SearchExpressionType[] { lessThanOrEqualTo, IsGreaterThanOrEqual };
restriction.Item = andType;
findItemRequest.Restriction = restriction;

希望有一天这会对某人有所帮助；-）
如果将来有人偶然发现这一点，EWS对日期格式的要求会更严格。公认的答案格式适用于两位数的月份，但不适用于一位数的月份

在所有情况下都适用的格式是：

DateTime.Today.AddDays(15).ToString("yyyy-MM-ddThh:mm:ssZ")

该限制还可以使用“可排序的日期/时间模式”

异常是在哪一行引发的？代码太多了。你需要能够识别问题发生在哪里，而不是发布整个程序。是的，很抱歉，但因为我不知道问题出在哪里，所以我发布了所有代码。异常位于带星星的那一行*********和vfipt的值为null。在深度调试会话之后，我发现responseMessage.MessageText具有以下内容“指定的值对于属性无效”。指定的值为“FieldURI”。这是MessageXml属性值：并且该值为null。
Datetime.Now.ToString("s")