The FindItem operation (or the corresponding ExchangeService.FindItems method) does not return the body of an email by default. And when trying to explicitly request them via a custom propertyset, the call fails. Consider this method, which uses the EWS Managed API to execute a FindItems method to get every message from the inbox folder of a mailbox, fetching only the item id and the body:
1: private static void GetAllItems(ExchangeService exchangeService)
2: {
3: var offset = 0;
4: const int pageSize = 100;
5:
6: FindItemsResults<Item> result;
7: do
8: {
9: var view = new ItemView(pageSize, offset)
10: {
11: PropertySet = new PropertySet(BasePropertySet.IdOnly)
12: {
13: ItemSchema.Body
14: }
15: };
16:
17: result = exchangeService.FindItems(WellKnownFolderName.Inbox, view);
18:
19: foreach (var item in result)
20: {
21: ProcessItem(item);
22: }
23: offset += pageSize;
24: } while (result.MoreAvailable);
25: }
When executed, the ExchangeService instance throws a ServiceValidationException stating “The property Body cannot be used in FindItem requests”. The official workaround proposed by Microsoft is to use a FindItem request to get the item ids of the items in a folder and afterward issue a GetItem request containing all the item ids and request the body property. However, there is another solution: The body properties can be fetched by requesting the MAPI properties containing the body:
1: private static ExtendedPropertyDefinition TextBodyProperty = new ExtendedPropertyDefinition(0x1000, MapiPropertyType.String);
2: private static ExtendedPropertyDefinition HtmlBodyProperty = new ExtendedPropertyDefinition(0x1013, MapiPropertyType.Binary);
The first property definition can be used to fetch the text body of a mail. The second one fetches the Html body. The new GetAllItemsMethod now looks like this:
1: private static void GetAllItems(ExchangeService exchangeService)
2: {
3: var offset = 0;
4: const int pageSize = 100;
5:
6: FindItemsResults<Item> result;
7: do
8: {
9: var view = new ItemView(pageSize, offset)
10: {
11: PropertySet = new PropertySet(BasePropertySet.IdOnly)
12: {
13: HtmlBodyProperty
14: }
15: };
16:
17: result = exchangeService.FindItems(WellKnownFolderName.Inbox, view);
18:
19: foreach (var item in result)
20: {
21: object body;
22: if (item.ExtendedProperties.TryGetValue(HtmlBodyProperty, out body))
23: {
24: Console.Out.WriteLine("item.Body = {0}", Encoding.UTF8.GetString(Convert.FromBase64String((string)body)));
25: }
26: }
27: offset += pageSize;
28: } while (result.MoreAvailable);
29: }
The HtmlBody is requested with the addtion of the HtmlBodyProperty to the ItemView in line 13. Since the Html body is stored in binary form and returned in Base64 encoded format, it needs to be decoded before it can be displayed. This is done in line 24. If the plaintext body is requested, the value of the body property in line 24 can simply be converted to a string.