AddAttachment Method
Adds an attachment to a specific item of a list.
Syntax
int AddAttachment(char* lpszItemId, char* lpszFileName);
Remarks
AddAttachment uploads the attachment specified by FileName to the item specified by ItemId.
If AllowLocalFile is set to True and LocalFile is specified, LocalFile will be uploaded. In this case the FileName parameter specifies the name of the file in SharePoint.