Can we create Extended attribute to a message on Exchange server?
Yes the API supports adding and retrieving Extended Attributes information to message on Exchange server. Please have a look at the following code sample for your kind reference.
Sample Code
NetworkCredential credential = new NetworkCredential(username, password, domain);
IEWSClient client = EWSClient.GetEWSClient(mailboxURI, credential);
{
try
{
//Create a new Property
PidNamePropertyDescriptor pd = new PidNamePropertyDescriptor(
"MyTestProp",
PropertyDataType.String,
KnownPropertySets.PublicStrings);
string value = "MyTestPropValue";
//Create a message
MapiMessage message = new MapiMessage(
"from@domain.com",
"to@domain.com",
"EMAILNET-38844 - " + Guid.NewGuid().ToString(),
"EMAILNET-38844 EWS: Support for create, retrieve and update Extended Attributes for Emails");
//Set property on the message
message.SetProperty(pd, value);
//append the message to server
string uri = client.AppendMessage(message);
//Fetch the message from server
MapiMessage mapiMessage = client.FetchMapiMessage(uri, new PropertyDescriptor[] { pd });
//Retreive the value from Message
string fetchedValue = mapiMessage.NamedProperties[pd].GetString();
}
finally
{
}
}