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Get attachments by using EWS in Exchange

Learn how to get attachments from EWS items by using the EWS Managed API or EWS in Exchange.

You can get attachments from an item by using the EWS Managed API or EWS. Because the initial call to get an item only includes metadata about the attachment collection on the item, retrieving attachments is always a two-step process. First, retrieve the item. Next, retrieve the attachment.

Table 1. EWS Managed API methods and EWS operations for adding attachments

Task EWS Managed API method EWS operation
Get item attachments
Item.Bind followed by ItemAttachment.Load
GetItem followed by GetAttachment
Get file attachments
Item.Bind followed by FileAttachment.Load
GetItem followed by GetAttachment

Get attachments from an email by using the EWS Managed API

The following code example shows how to get an EmailMessage object by using the Bind method, then iterate through the attachment collection and call the FileAttachment.Load or ItemAttachment.Load method on each attachment as appropriate. Each file attachment is saved to the C:\temp\ folder, and each item attachment is loaded into memory. For information about how to save an item attachment, see Save an attached email by using the EWS Managed API.

This example assumes that service is a valid ExchangeService object, that itemId is the ItemId of the message from which attachments will be retrieved, and that the user has been authenticated to an Exchange server.

public static void GetAttachmentsFromEmail(ExchangeService service, ItemId itemId)
{
    // Bind to an existing message item and retrieve the attachments collection.
    // This method results in an GetItem call to EWS.
    EmailMessage message = EmailMessage.Bind(service, itemId, new PropertySet(ItemSchema.Attachments));
    // Iterate through the attachments collection and load each attachment.
    foreach (Attachment attachment in message.Attachments)
    {
        if (attachment is FileAttachment)
        {
            FileAttachment fileAttachment = attachment as FileAttachment;
            // Load the attachment into a file.
            // This call results in a GetAttachment call to EWS.
            fileAttachment.Load("C:\\temp\\" + fileAttachment.Name);
           
            Console.WriteLine("File attachment name: " + fileAttachment.Name);
        }
        else // Attachment is an item attachment.
        {
            ItemAttachment itemAttachment = attachment as ItemAttachment;
            // Load attachment into memory and write out the subject.
            // This does not save the file like it does with a file attachment.
            // This call results in a GetAttachment call to EWS.
            itemAttachment.Load();
            Console.WriteLine("Item attachment name: " + itemAttachment.Name);
        }
    }
}

Get an attachment from an email by using EWS

To get attachments by using EWS, you first need to retrieve the message and the attachment collection to get the AttachmentId (GetAttachment and DeleteAttachment) of the attachment to retrieve. After you have one or more AttachmentId values to retrieve, call the GetAttachment operation to load all the properties for the attachment.

The following code example shows how to use the GetItem operation to get an email message and the collection of attachments on the message. This is also the first XML request that the EWS Managed API sends when you use the EWS Managed API to get all attachments from an email. The values of some attributes are shortened for readability.

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
               xmlns:m="http://schemas.microsoft.com/exchange/services/2006/messages"
               xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types"
               xmlns:soap="https://schemas.xmlsoap.org/soap/envelope/">
  <soap:Header>
    <t:RequestServerVersion Version="Exchange207_SP1" />
  </soap:Header>
  <soap:Body>
    <m:GetItem>
      <m:ItemShape>
        <t:BaseShape>IdOnly</t:BaseShape>
        <t:AdditionalProperties>
          <t:FieldURI FieldURI="item:Attachments" />
        </t:AdditionalProperties>
      </m:ItemShape>
      <m:ItemIds>
        <t:ItemId Id="ERu/AAA=" />
      </m:ItemIds>
    </m:GetItem>
  </soap:Body>
</soap:Envelope>

The server responds to the GetItem request with a GetItemResponse message that includes a ResponseCode value of NoError, which indicates that the email was retrieved successfully, and the AttachmentId values of the existing attachments.

<?xml version="1.0" encoding="utf-8"?>
<s:Envelope xmlns:s="https://schemas.xmlsoap.org/soap/envelope/">
  <s:Header>
    <h:ServerVersionInfo MajorVersion="15"
                         MinorVersion="0"
                         MajorBuildNumber="939"
                         MinorBuildNumber="12"
                         Version="V2_11"
                         xmlns:h="http://schemas.microsoft.com/exchange/services/2006/types"
                         xmlns="http://schemas.microsoft.com/exchange/services/2006/types"
                         xmlns:xsd="http://www.w3.org/2001/XMLSchema"
                         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" />
  </s:Header>
  <s:Body xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xmlns:xsd="http://www.w3.org/2001/XMLSchema">
    <m:GetItemResponse xmlns:m="http://schemas.microsoft.com/exchange/services/2006/messages"
                       xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types">
      <m:ResponseMessages>
        <m:GetItemResponseMessage ResponseClass="Success">
          <m:ResponseCode>NoError</m:ResponseCode>
          <m:Items>
            <t:Message>
              <t:ItemId Id="ERu/AAA="
                        ChangeKey="CQAAABYAAAAFI5DJmZv+TLtyLOLIF1S5AAAYEMnd" />
              <t:Attachments>
                <t:FileAttachment>
                  <t:AttachmentId Id="5zTzlqU=" />
                  <t:Name>FileAttachment.txt</t:Name>
                  <t:Size>212</t:Size>
                  <t:LastModifiedTime>2014-05-14T17:59:30</t:LastModifiedTime>
                  <t:IsInline>false</t:IsInline>
                  <t:IsContactPhoto>false</t:IsContactPhoto>
                </t:FileAttachment>
                <t:ItemAttachment>
                  <t:AttachmentId Id="Ktum21o=" />
                  <t:Name>Attached Message Item</t:Name>
                  <t:Size>3063</t:Size>
                  <t:LastModifiedTime>2014-05-14T17:59:30</t:LastModifiedTime>
                  <t:IsInline>false</t:IsInline>
                </t:ItemAttachment>
              </t:Attachments>
            </t:Message>
          </m:Items>
        </m:GetItemResponseMessage>
      </m:ResponseMessages>
    </m:GetItemResponse>
  </s:Body>
</s:Envelope>

Now that you have the AttachmentId values, call GetAttachment on each attachment you want to retrieve.

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
               xmlns:m="http://schemas.microsoft.com/exchange/services/2006/messages"
               xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types"
               xmlns:soap="https://schemas.xmlsoap.org/soap/envelope/">
  <soap:Header>
    <t:RequestServerVersion Version="Exchange2007_SP1" />
  </soap:Header>
  <soap:Body>
    <m:GetAttachment>
      <m:AttachmentIds>
        <t:AttachmentId Id="5zTzlqU=" />
      </m:AttachmentIds>
    </m:GetAttachment>
  </soap:Body>
</soap:Envelope>

When retrieving an item attachment, the server responds to the GetAttachment request with a GetAttachmentResponse message that includes a ResponseCode value of NoError, which indicates that the attachment was retrieved successfully, and all the elements for the attached item, which in this case is an email message.

<?xml version="1.0" encoding="utf-8"?>
<s:Envelope xmlns:s="https://schemas.xmlsoap.org/soap/envelope/">
  <s:Header>
    <h:ServerVersionInfo MajorVersion="15"
                         MinorVersion="0"
                         MajorBuildNumber="939"
                         MinorBuildNumber="12"
                         Version="V2_11"
                         xmlns:h="http://schemas.microsoft.com/exchange/services/2006/types"
                         xmlns="http://schemas.microsoft.com/exchange/services/2006/types"
                         xmlns:xsd="http://www.w3.org/2001/XMLSchema"
                         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" />
  </s:Header>
  <s:Body xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xmlns:xsd="http://www.w3.org/2001/XMLSchema">
    <m:GetAttachmentResponse xmlns:m="http://schemas.microsoft.com/exchange/services/2006/messages"
                             xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types">
      <m:ResponseMessages>
        <m:GetAttachmentResponseMessage ResponseClass="Success">
          <m:ResponseCode>NoError</m:ResponseCode>
          <m:Attachments>
            <t:ItemAttachment>
              <t:AttachmentId Id="Ktum21o=" />
              <t:Name>Attached Message Item</t:Name>
              <t:Message>
                <t:ItemClass>IPM.Note</t:ItemClass>
                <t:Subject>Message Item Subject</t:Subject>
                <t:Body BodyType="HTML">&amp;lt;meta http-equiv="Content-Type" 
                    content="text/html; charset=utf-8"&amp;gt;Message Item Body</t:Body>
                <t:Size>2859</t:Size>
                <t:IsSubmitted>false</t:IsSubmitted>
                <t:IsDraft>true</t:IsDraft>
                <t:IsFromMe>false</t:IsFromMe>
                <t:IsResend>false</t:IsResend>
                <t:IsUnmodified>false</t:IsUnmodified>
                <t:DateTimeCreated>2014-05-14T17:59:37Z</t:DateTimeCreated>
                <t:ResponseObjects>
                  <t:ForwardItem />
                </t:ResponseObjects>
                <t:DisplayCc />
                <t:DisplayTo>primary; emaildelegate</t:DisplayTo>
                <t:HasAttachments>false</t:HasAttachments>
                <t:Culture>en</t:Culture>
                <t:EffectiveRights>
                  <t:CreateAssociated>false</t:CreateAssociated>
                  <t:CreateContents>false</t:CreateContents>
                  <t:CreateHierarchy>false</t:CreateHierarchy>
                  <t:Delete>true</t:Delete>
                  <t:Modify>true</t:Modify>
                  <t:Read>true</t:Read>
                </t:EffectiveRights>
                <t:LastModifiedName>primary</t:LastModifiedName>
                <t:LastModifiedTime>2014-05-14T17:59:30Z</t:LastModifiedTime>
                <t:IsAssociated>false</t:IsAssociated>
                <t:WebClientReadFormQueryString>?ItemID=AAMk3D&amp;amp;exvsurl=1&amp;amp;viewmodel=
                    ReadMessageItem</t:WebClientReadFormQueryString>
                <t:ConversationId Id="AAQkADIwM2ZlM2ZlLWMwYjctNDg2N/Rc+d0=" />
                <t:ToRecipients>
                  <t:Mailbox>
                    <t:Name>primary</t:Name>
                    <t:EmailAddress>sadie@contoso.com</t:EmailAddress>
                    <t:RoutingType>SMTP</t:RoutingType>
                    <t:MailboxType>Mailbox</t:MailboxType>
                  </t:Mailbox>
                  <t:Mailbox>
                    <t:Name>emaildelegate</t:Name>
                    <t:EmailAddress>ronnie@contoso.com</t:EmailAddress>
                    <t:RoutingType>SMTP</t:RoutingType>
                    <t:MailboxType>Mailbox</t:MailboxType>
                  </t:Mailbox>
                </t:ToRecipients>
                <t:IsReadReceiptRequested>false</t:IsReadReceiptRequested>
                <t:ConversationIndex>AQHPb55BxR5Fm0Arx0yY4xbL9Fz53Q==</t:ConversationIndex>
                <t:ConversationTopic>Message Item Subject</t:ConversationTopic>
                <t:IsRead>true</t:IsRead>
              </t:Message>
            </t:ItemAttachment>
          </m:Attachments>
        </m:GetAttachmentResponseMessage>
      </m:ResponseMessages>
    </m:GetAttachmentResponse>
  </s:Body>
</s:Envelope>

When retrieving a file attachment, the server responds to the GetAttachment request with a GetAttachmentResponse message that includes a ResponseCode value of NoError, which indicates that the attachment was retrieved successfully, and all the elements of the file attachment.

<?xml version="1.0" encoding="utf-8"?>
<s:Envelope xmlns:s="https://schemas.xmlsoap.org/soap/envelope/">
  <s:Header>
    <h:ServerVersionInfo MajorVersion="15"
                         MinorVersion="0"
                         MajorBuildNumber="939"
                         MinorBuildNumber="12"
                         Version="V2_11"
                         xmlns:h="http://schemas.microsoft.com/exchange/services/2006/types"
                         xmlns="http://schemas.microsoft.com/exchange/services/2006/types"
                         xmlns:xsd="http://www.w3.org/2001/XMLSchema"
                         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" />
  </s:Header>
  <s:Body xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xmlns:xsd="http://www.w3.org/2001/XMLSchema">
    <m:GetAttachmentResponse xmlns:m="http://schemas.microsoft.com/exchange/services/2006/messages"
                             xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types">
      <m:ResponseMessages>
        <m:GetAttachmentResponseMessage ResponseClass="Success">
          <m:ResponseCode>NoError</m:ResponseCode>
          <m:Attachments>
            <t:FileAttachment>
              <t:AttachmentId Id="5zTzlqU=" />
              <t:Name>FileAttachment.txt</t:Name>
              <t:Content>VGhpcyBpcyBhIGZpbGUgYXR0YWNobWVudC4=</t:Content>
            </t:FileAttachment>
          </m:Attachments>
        </m:GetAttachmentResponseMessage>
      </m:ResponseMessages>
    </m:GetAttachmentResponse>
  </s:Body>
</s:Envelope>

Save an attached email by using the EWS Managed API

In order to save the contents of an email attachment using the EWS Managed API, you need to save the MimeContent to a file. In doing so, you will lose any extended properties set on the item, such as follow-up flags and categories. This example saves the email attachment to the to the C:\temp\ folder.

Note that you cannot move or copy the item attachment to another folder because the item attachment is not a strongly-typed item, so if you're trying to move an attachment to a different folder, use the following code example and then import the file into a different folder.

public static void SaveEmailAttachment(ExchangeService service, ItemId itemId)
{
    // Bind to an existing message item and retrieve the attachments collection.
    // This method results in an GetItem call to EWS.
    EmailMessage message = EmailMessage.Bind(service, itemId, new PropertySet(ItemSchema.Attachments));
    
    foreach (Attachment attachment in message.Attachments)
    {
        if (attachment is ItemAttachment)
        {
            ItemAttachment itemAttachment = attachment as ItemAttachment;
            itemAttachment.Load(ItemSchema.MimeContent);
            string fileName = "C:\\Temp\\" + itemAttachment.Item.Subject + ".eml";
            // Write the bytes of the attachment into a file.
            File.WriteAllBytes(fileName, itemAttachment.Item.MimeContent.Content);
            Console.WriteLine("Email attachment name: "+ itemAttachment.Item.Subject + ".eml");
        }
    }
}

See also