private CoreAttachment InternalCreate(AttachmentType?type, string itemClass, CoreAttachment attachmentToClone, IItem itemToAttach)
{
this.InitCollection("InternalCreate", true);
AttachmentPropertyBag attachmentPropertyBag = null;
CoreAttachment coreAttachment = null;
bool flag = false;
try
{
bool flag2 = false;
if (attachmentToClone != null)
{
flag2 = this.attachmentProvider.SupportsCreateClone(attachmentToClone.PropertyBag);
}
attachmentPropertyBag = this.InternalCreateAttachmentPropertyBag(type, flag2 ? attachmentToClone : null, itemToAttach);
if (itemClass != null)
{
((IDirectPropertyBag)attachmentPropertyBag).SetValue(InternalSchema.ItemClass, itemClass);
}
AttachmentHandle attachmentHandle = new AttachmentHandle(attachmentPropertyBag.AttachmentNumber);
coreAttachment = new CoreAttachment(this, attachmentPropertyBag, Origin.New);
attachmentPropertyBag = null;
if (attachmentToClone != null && !flag2)
{
coreAttachment.CopyAttachmentContentFrom(attachmentToClone);
}
this.newAttachmentNumberMap.Add(attachmentHandle.AttachNumber, attachmentHandle);
flag = true;
}
finally
{
if (!flag)
{
if (coreAttachment != null)
{
coreAttachment.Dispose();
coreAttachment = null;
}
if (attachmentPropertyBag != null)
{
attachmentPropertyBag.Dispose();
attachmentPropertyBag = null;
}
}
}
return(coreAttachment);
}
internal Attachment Open(AttachmentHandle handle, AttachmentType?type, ICollection <PropertyDefinition> propertyDefinitions)
{
Util.ThrowOnNullArgument(handle, "handle");
if (type != null)
{
EnumValidator.ThrowIfInvalid <AttachmentType>(type.Value, "type");
}
Attachment attachment = null;
CoreAttachment coreAttachment = null;
try
{
coreAttachment = this.CoreAttachmentCollection.Open(handle, propertyDefinitions);
attachment = AttachmentCollection.CreateTypedAttachment(coreAttachment, type);
}
finally
{
if (attachment == null && coreAttachment != null)
{
coreAttachment.Dispose();
}
}
return(attachment);
}