Basically we have two ways to read email from on-premise Exchange. The first option is utilizing Exchange Web Service managed API. It can be used for both on-premise Exchange server and O365 (an example I blogged before). The other option is today's topic: Exchange Service Binding, which by any means, should be avoid! Now let's have a look the basic routine:
- find the root of the email account;
- locate the base email folder (normally it should be the inbox folder);
- pull emails from the base folder;
- get email attachments' id from the email item;
- pull attachments from email by attachment item id;
To locate the root folder of the account (NOT the inbox folder)
public static string GetRootFolder(ExchangeServiceBinding esb)
{
DistinguishedFolderIdType[] dfit = new DistinguishedFolderIdType[1];
dfit[0] = new DistinguishedFolderIdType();
dfit[0].Id = DistinguishedFolderIdNameType.root;
FolderResponseShapeType frst = new FolderResponseShapeType();
frst.BaseShape = DefaultShapeNamesType.AllProperties;
GetFolderType gftRoot = new GetFolderType();
gftRoot.FolderIds = dfit;
gftRoot.FolderShape = frst;
GetFolderResponseType gfrt = esb.GetFolder(gftRoot);
FolderInfoResponseMessageType firmt = ((FolderInfoResponseMessageType)gfrt.ResponseMessages.Items[0]);
if (firmt.ResponseClass == ResponseClassType.Success)
return ((FolderInfoResponseMessageType)gfrt.ResponseMessages.Items[0]).Folders[0].FolderId.Id;
else
return null;
}
After we have the root, we can navigate to the specific folder by folder name, inbox, archive, deleted folder, whatever you like :)
public static BaseFolderType GetFolder(ExchangeServiceBinding esb, string parentFolderId, string folderName)
{
if (esb == null || string.IsNullOrEmpty(parentFolderId))
return null;
FolderIdType[] fit = new FolderIdType[1];
fit[0] = new FolderIdType();
fit[0].Id = parentFolderId;
FolderResponseShapeType frst = new FolderResponseShapeType();
frst.BaseShape = DefaultShapeNamesType.AllProperties;
PathToUnindexedFieldType ftFolderName = new PathToUnindexedFieldType();
ftFolderName.FieldURI = UnindexedFieldURIType.folderDisplayName;
ConstantValueType cvt = new ConstantValueType();
cvt.Value = folderName;
FieldURIOrConstantType ctFolderName = new FieldURIOrConstantType();
ctFolderName.Item = cvt;
ContainsExpressionType cet = new ContainsExpressionType();
cet.Constant = cvt;
cet.Item = ftFolderName;
cet.ContainmentComparison = ContainmentComparisonType.IgnoreCase;
cet.ContainmentComparisonSpecified = true;
cet.ContainmentMode = ContainmentModeType.FullString;
cet.ContainmentModeSpecified = true;
RestrictionType rt = new RestrictionType();
rt.Item = cet;
FindFolderType fft = new FindFolderType();
fft.Traversal = FolderQueryTraversalType.Deep;
fft.ParentFolderIds = fit;
fft.FolderShape = frst;
fft.Restriction = rt;
FindFolderResponseType ffrt = esb.FindFolder(fft);
ResponseMessageType rmt = ((ResponseMessageType)ffrt.ResponseMessages.Items[0]);
if (rmt.ResponseClass == ResponseClassType.Success)
{
BaseFolderType[] bfts = ((FindFolderResponseMessageType)ffrt.ResponseMessages.Items[0]).RootFolder.Folders;
if (bfts.GetLength(0) > 0)
return bfts[0];
else
return null;
}
else
return null;
}
Now we can get all email items from the folder we located
public static ListGetEmailItems(ExchangeServiceBinding esb) { List lstItems = new List (); FindItemType fitRequest = new FindItemType(); fitRequest.Traversal = ItemQueryTraversalType.Shallow; ItemResponseShapeType irst = new ItemResponseShapeType(); irst.BaseShape = DefaultShapeNamesType.AllProperties; fitRequest.ItemShape = irst; DistinguishedFolderIdType[] dfits = new DistinguishedFolderIdType[1]; dfits[0] = new DistinguishedFolderIdType(); dfits[0].Id = DistinguishedFolderIdNameType.inbox; fitRequest.ParentFolderIds = dfits; FindItemResponseType fitResponse = esb.FindItem(fitRequest); FindItemResponseMessageType findItemResponseMessageType = (FindItemResponseMessageType)fitResponse.ResponseMessages.Items[0]; var responseContents = findItemResponseMessageType.RootFolder.Item; var items = ((ArrayOfRealItemsType)responseContents).Items; if (items != null && items.Length > 0) { foreach (var item in items) { lstItems.Add(item); } } return lstItems; }
Now here is a very important concept: if you google Exchange Service Binding, you will find the concept of the attachment in ESB is a bid confusing: the Attachments property returned from email ItemType is not the actual attachment itself. So we need to get the item id of the attachment, then we can get the actual attachment from the item id. Below is the code to construct a dictionary object for attachment id and attachment name:
public static DictionaryGetAttachments(ExchangeServiceBinding esb, ItemIdType itemId) { Dictionary attachments = new Dictionary (); GetItemType gitRequest = new GetItemType(); gitRequest.ItemIds = new ItemIdType[] { itemId }; gitRequest.ItemShape = new ItemResponseShapeType(); gitRequest.ItemShape.BaseShape = DefaultShapeNamesType.AllProperties; PathToUnindexedFieldType hasAttachPath = new PathToUnindexedFieldType(); hasAttachPath.FieldURI = UnindexedFieldURIType.itemHasAttachments; PathToUnindexedFieldType attachmentsPath = new PathToUnindexedFieldType(); attachmentsPath.FieldURI = UnindexedFieldURIType.itemAttachments; gitRequest.ItemShape.AdditionalProperties = new BasePathToElementType[] { hasAttachPath, attachmentsPath }; GetItemResponseType giResponse = esb.GetItem(gitRequest); ItemInfoResponseMessageType iirm = (ItemInfoResponseMessageType)giResponse.ResponseMessages.Items[0]; if (iirm.ResponseCode == ResponseCodeType.NoError) { ItemType it = iirm.Items.Items[0]; if (it.HasAttachments && it.Attachments != null && it.Attachments.Length > 0) { foreach (AttachmentType attachmentItem in it.Attachments) { FileAttachmentType fat = (FileAttachmentType)attachmentItem; if (fat != null) { attachments.Add(fat.AttachmentId.Id, fat.Name); } } } } return attachments; }
Then we can get the attachment and save to the disk
public static void GetAttachmentsOnItem(ExchangeServiceBinding esb, ItemIdType itemId, string destPath)
{
GetItemType gitRequest = new GetItemType();
gitRequest.ItemIds = new ItemIdType[] { itemId };
gitRequest.ItemShape = new ItemResponseShapeType();
gitRequest.ItemShape.BaseShape = DefaultShapeNamesType.IdOnly;
PathToUnindexedFieldType hasAttachPath = new PathToUnindexedFieldType();
hasAttachPath.FieldURI = UnindexedFieldURIType.itemHasAttachments;
PathToUnindexedFieldType attachmentsPath = new PathToUnindexedFieldType();
attachmentsPath.FieldURI = UnindexedFieldURIType.itemAttachments;
gitRequest.ItemShape.AdditionalProperties = new BasePathToElementType[] { hasAttachPath, attachmentsPath };
GetItemResponseType getItemResponse = esb.GetItem(gitRequest);
ItemInfoResponseMessageType getItemResponseMessage = (ItemInfoResponseMessageType)getItemResponse.ResponseMessages.Items[0];
if (getItemResponseMessage.ResponseCode == ResponseCodeType.NoError)
{
ItemType item = getItemResponseMessage.Items.Items[0];
if (item.HasAttachments && (item.Attachments != null) && (item.Attachments.Length > 0))
{
List lstRait = new List();
for (int attachmentIndex = 0; attachmentIndex < item.Attachments.Length; attachmentIndex++)
{
FileAttachmentType fat = (FileAttachmentType)item.Attachments[attachmentIndex];
if (fat != null)
{
RequestAttachmentIdType rait = new RequestAttachmentIdType();
rait.Id = fat.AttachmentId.Id;
lstRait.Add(rait);
}
}
GetAttachmentType gat = new GetAttachmentType();
gat.AttachmentShape = new AttachmentResponseShapeType();
gat.AttachmentIds = lstRait.ToArray();
GetAttachmentResponseType getAttachmentResponse = esb.GetAttachment(gat);
foreach (AttachmentInfoResponseMessageType attachmentResponseMessage in getAttachmentResponse.ResponseMessages.Items)
{
if (attachmentResponseMessage.ResponseCode == ResponseCodeType.NoError)
{
FileAttachmentType fileAttachment = attachmentResponseMessage.Attachments[0] as FileAttachmentType;
using (FileStream file = File.Create(Path.Combine(destPath, fileAttachment.Name)))
{
file.Write(fileAttachment.Content, 0, fileAttachment.Content.Length);
file.Flush();
file.Close();
}
}
}
}
}
}
No comments :
Post a Comment