Versioning EWS requests by using the EWS Managed API 2.0

Example

This section includes examples of successful and unsuccessful request versioning.

Successful Versioning

static void UsingVersioning()
{
   // Connect to Exchange Web Services as user1 at contoso.com, targeting Exchange 2010.
   ExchangeService service = new ExchangeService(ExchangeVersion.Exchange2010);
   service.Credentials = new WebCredentials("user1", "password", "contoso.com");
   service.AutodiscoverUrl("user1@contoso.com");

   try
   {
      // Create and save a folder associated message in the Inbox. 
      EmailMessage message = new EmailMessage(service);
      message.IsAssociated = true;
      message.Subject = "Interesting subject";
      message.Save(WellKnownFolderName.Inbox);

      // Write confirmation message to the console window.
      Console.WriteLine("Folder associated message created & saved.");
      Console.ReadLine();
   }
   catch (Exception ex)
   {
      // Write error message to the console window.
      Console.WriteLine("Error: " + ex.Message);
      Console.ReadLine();
   }
}

The following example shows the XML that is sent by using the Save method.

<?xml version="1.0" encoding="utf-8" ?> 
   <soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"          
                  xmlns:m="https://schemas.microsoft.com/exchange/services/2006/messages" 
                  xmlns:t="https://schemas.microsoft.com/exchange/services/2006/types" xmlns:soap="https://schemas.xmlsoap.org/soap/envelope/"> 
      <soap:Header> 
         <t:RequestServerVersion Version="Exchange2010" /> 
      </soap:Header> 
      <soap:Body> 
         <m:CreateItem MessageDisposition="SaveOnly"> 
            <m:SavedItemFolderId> 
               <t:DistinguishedFolderId Id="Inbox" /> 
            </m:SavedItemFolderId> 
            <m:Items> 
               <t:Message> 
                  <t:Subject>Interesting</t:Subject> 
                  <t:IsAssociated>true</t:IsAssociated> 
               </t:Message> 
            </m:Items> 
         </m:CreateItem> 
      </soap:Body> 
   </soap:Envelope>

The following example shows the XML that is returned by using the Save method. The ItemId and ChangeKey attributes have been shortened to preserve readability.

<?xml version="1.0" encoding="utf-8" ?> 
   <s:Envelope xmlns:s="https://schemas.xmlsoap.org/soap/envelope/"> 
      <s:Header> 
         <h:ServerVersionInfo MajorVersion="14" MinorVersion="0" MajorBuildNumber="478" MinorBuildNumber="0" Version="Exchange2010" 
               xmlns:h="https://schemas.microsoft.com/exchange/services/2006/types" 
               xmlns="https://schemas.microsoft.com/exchange/services/2006/types" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
               xmlns:xsd="http://www.w3.org/2001/XMLSchema" /> 
      </s:Header> 
      <s:Body xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"> 
         <m:CreateItemResponse xmlns:m="https://schemas.microsoft.com/exchange/services/2006/messages"    
                               xmlns:t="https://schemas.microsoft.com/exchange/services/2006/types"> 
            <m:ResponseMessages> 
               <m:CreateItemResponseMessage ResponseClass="Success"> 
                  <m:ResponseCode>NoError</m:ResponseCode> 
                     <m:Items> 
                        <t:Message> 
                           <t:ItemId Id="AQMkAGY" ChangeKey="CQAAA " /> 
                        </t:Message> 
                     </m:Items> 
               </m:CreateItemResponseMessage> 
            </m:ResponseMessages> 
         </m:CreateItemResponse> 
      </s:Body> 
   </s:Envelope>

Unsuccessful Versioning

static void UsingVersioning()
{
   // Connect to Exchange Web Services as user1 at contoso.com, targeting Exchange 2007 SP1.
   ExchangeService service = new ExchangeService(ExchangeVersion.Exchange2007_SP1);
   service.Credentials = new WebCredentials("user1", "password", "contoso.com");
   service.AutodiscoverUrl("user1@contoso.com");

   try
   {
      // Create and save a folder associated message in the Inbox. 
      EmailMessage message = new EmailMessage(service);
      message. IsAssociated = true;
      message.Subject = "Interesting subject";
      message.Save(WellKnownFolderName.Inbox);

      // Write confirmation message to the console window.
      Console.WriteLine("Folder associated message created & saved.");
      Console.ReadLine();
   }
   catch (Exception ex)
   {
      // Write error message to the console window.
      Console.WriteLine("Error: " + ex.Message);
      Console.ReadLine();
   }
}

Robust programming

• Write appropriate error handling code for common search errors.

• Review the client request XML that is sent to the Exchange server.

• Review the server response XML that is sent from the Exchange server.

Security

• Use HTTP with SSL for all communication between client and server.

• Always validate the server certificate that is used to establish the SSL connections. For more information, see Validating X509 certificates by using the EWS Managed API 2.0.

• Do not include user names and passwords in trace files.

• Ensure that Autodiscover lookups that use HTTP GET to find an endpoint always prompt for user confirmation; otherwise, they should be blocked.

See also

Concepts