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Delete attachments by using EWS in Exchange

  • Artikkeli

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

You have a number of options when it comes to deleting file and item attachments from items by using the EWS Managed API. You can delete all the attachments from the message, delete by a file name, or delete by position in the collection. For each of these options, there is an AttachmentCollection method.

Conversely, with EWS, no matter whether you're deleting all attachments from an item or just one, the sequence of operations is same. Unlike the EWS Managed API, EWS does not include separate operations to delete based on name or position in the attachments array.

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

Task EWS Managed API method EWS operation
Delete all attachments from an item.
Item.Bind, followed by AttachmentCollection.Clear, followed by EmailMessage.Update
GetItem followed by DeleteAttachment
Delete an attachment from an item by name.
Item.Bind, followed by AttachmentCollection.Remove, followed by EmailMessage.Update
GetItem followed by DeleteAttachment
Delete an attachment from an item by position in the collection.
Item.Bind, followed by AttachmentCollection.RemoveAt, followed by EmailMessage.Update
GetItem followed by DeleteAttachment

Delete all attachments from an email by using the EWS Managed API

The following code example shows how to delete all attachments from an email by:

  1. Using the EmailMessage.Bind method to bind to an existing email message and retrieve the collection of Attachments.

  2. Using the AttachmentCollection.Clear method to delete all the attachments from the email.

  3. Using the EmailMessage.Update method to save the changes.

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

public static void DeleteAllAttachments(ExchangeService service, ItemId itemId)
{
    // Bind to an existing message by using its item ID and requesting its attachments collection.
    // This method results in a GetItem call to EWS.
    EmailMessage message = EmailMessage.Bind(service, itemId, new PropertySet(ItemSchema.Attachments));
    // Delete all attachments from the message.
    message.Attachments.Clear();
    // Save the updated message.
    // This method results in an DeleteAttachment call to EWS.
    message.Update(ConflictResolutionMode.AlwaysOverwrite);
}

Delete an attachment by name from an email by using the EWS Managed API

The following code example shows how delete an attachment by name by:

  1. Using the EmailMessage.Bind method to bind to an existing email message and retrieve the collection of Attachments.

  2. Using the AttachmentCollection.Remove method to delete an attachment named FileAttachment.txt.

  3. Using the EmailMessage.Update method to save the changes.

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

public static void DeleteNamedAttachments(ExchangeService service, ItemId itemId)
{
    // Bind to an existing message by using its item ID and requesting its attachments collection.
    // This method results in a GetItem call to EWS.
    EmailMessage message = EmailMessage.Bind(service, itemId, new PropertySet(ItemSchema.Attachments));
    // Iterate through the attachments collection and delete the attachment named "FileAttachment.txt," if it exists.
    foreach (Attachment attachment in message.Attachments)
    {
        if (attachment.Name == "FileAttachment.txt")
        {
            message.Attachments.Remove(attachment);
            break;
        }
    }
    // Save the updated message.
    // This method results in an DeleteAttachment call to EWS.
    message.Update(ConflictResolutionMode.AlwaysOverwrite);
}

Delete attachments by position by using the EWS Managed API

The following code example shows how to delete an attachment by position by:

  1. Using the EmailMessage.Bind method to bind to an existing email message and retrieve the collection of Attachments and the EmailMessage.HasAttachments property.

  2. Using the AttachmentCollection.Remove method to delete the first attachment in the collection.

  3. Using the EmailMessage.Update method to save the changes.

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

public static void DeleteAttachmentByPosition(ExchangeService service, ItemId itemId)
{
    // Bind to an existing message by using its item ID and requesting the HasAttachments property and the attachments collection.
    // This method results in a GetItem call to EWS.
    EmailMessage message = EmailMessage.Bind(service, itemId, new PropertySet(EmailMessageSchema.HasAttachments, ItemSchema.Attachments));
    // Remove attachments using the zero-based index position of the attachment in the attachments collection.
    if (message.HasAttachments)
    {
        message.Attachments.RemoveAt(0);
    }
    // Save the updated message.
    // This method results in an DeleteAttachment call to EWS.
    message.Update(ConflictResolutionMode.AlwaysOverwrite);
}

Delete attachments from an item by using EWS

To delete attachments by using EWS, you first need to retrieve the message and the attachment collection to determine the AttachmentId (GetAttachment and DeleteAttachment) of the attachment to delete. After you have one or more AttachmentId values to delete, call the DeleteAttachment operation to remove the specified attachments from the message.

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 delete 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="Exchange2007_SP1" />
    <t:TimeZoneContext>
      <t:TimeZoneDefinition Id="Central Standard Time" />
    </t:TimeZoneContext>
  </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="uqE1AAA=" />
      </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="uqE1AAA="
                        ChangeKey="CQAAABYAAAAFI5DJmZv+TLtyLOLIF1S5AAAXulcd" />
              <t:Attachments>
                <t:FileAttachment>
                  <t:AttachmentId Id="IpHLObE=" />
                  <t:Name>FileAttachment.txt</t:Name>
                </t:FileAttachment>
                <t:FileAttachment>
                  <t:AttachmentId Id="QuHSSmY=" />
                  <t:Name>SecondAttachment.txt</t:Name>
                </t:FileAttachment>
                <t:FileAttachment>
                  <t:AttachmentId Id="qf2KoPo=" />
                  <t:Name>ThirdAttachment.jpg</t:Name>
                </t:FileAttachment>
                <t:FileAttachment>
                  <t:AttachmentId Id="NFQMnMc=" />
                  <t:Name>FourthAttachment.txt</t:Name>
                </t:FileAttachment>
                <t:ItemAttachment>
                  <t:AttachmentId Id="jJvbLXQ=" />
                  <t:Name>Attached Message Item</t:Name>
                </t:ItemAttachment>
              </t:Attachments>
            </t:Message>
          </m:Items>
        </m:GetItemResponseMessage>
      </m:ResponseMessages>
    </m:GetItemResponse>
  </s:Body>
</s:Envelope>

After you determine which attachment to delete, call the DeleteAttachment operation and include the AttachmentId values of the attachments to delete.

<?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" />
    <t:TimeZoneContext>
      <t:TimeZoneDefinition Id="Central Standard Time" />
    </t:TimeZoneContext>
  </soap:Header>
  <soap:Body>
    <m:DeleteAttachment>
      <m:AttachmentIds>
        <t:AttachmentId Id="IpHLObE=" />
        <t:AttachmentId Id="QuHSSmY=" />
        <t:AttachmentId Id="qf2KoPo=" />
        <t:AttachmentId Id="NFQMnMc=" />
        <t:AttachmentId Id="jJvbLXQ=" />
      </m:AttachmentIds>
    </m:DeleteAttachment>
  </soap:Body>
</soap:Envelope>

The server responds to the DeleteAttachment request with a DeleteAttachmentResponse message that includes a ResponseCode value of NoError for each DeleteAttachmentResponseMessage, which indicates that each attachment was deleted successfully. The values of some attributes are shortened for readability.

<?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:DeleteAttachmentResponse xmlns:m="http://schemas.microsoft.com/exchange/services/2006/messages"
                                xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types">
      <m:ResponseMessages>
        <m:DeleteAttachmentResponseMessage ResponseClass="Success">
          <m:ResponseCode>NoError</m:ResponseCode>
          <m:RootItemId RootItemId="uqE1AAA=" RootItemChangeKey="AAAXulck" />
        </m:DeleteAttachmentResponseMessage>
        <m:DeleteAttachmentResponseMessage ResponseClass="Success">
          <m:ResponseCode>NoError</m:ResponseCode>
          <m:RootItemId RootItemId="uqE1AAA=" RootItemChangeKey="AAAXulck" />
        </m:DeleteAttachmentResponseMessage>
        <m:DeleteAttachmentResponseMessage ResponseClass="Success">
          <m:ResponseCode>NoError</m:ResponseCode>
          <m:RootItemId RootItemId="uqE1AAA=" RootItemChangeKey="AAAXulck" />
        </m:DeleteAttachmentResponseMessage>
        <m:DeleteAttachmentResponseMessage ResponseClass="Success">
          <m:ResponseCode>NoError</m:ResponseCode>
          <m:RootItemId RootItemId="uqE1AAA=" RootItemChangeKey="AAAXulck" />
        </m:DeleteAttachmentResponseMessage>
        <m:DeleteAttachmentResponseMessage ResponseClass="Success">
          <m:ResponseCode>NoError</m:ResponseCode>
          <m:RootItemId RootItemId="uqE1AAA=" RootItemChangeKey="AAAXulck" />
        </m:DeleteAttachmentResponseMessage>
      </m:ResponseMessages>
    </m:DeleteAttachmentResponse>
  </s:Body>
</s:Envelope>

See also