Item Updating or Item Updated Event in SharePoint 2007 occurs twice, if require checkout option is enabled for document library.
I found the following workaround from Microsoft Support for this issue.
Check the value of vti_sourcecontrolcheckedoutby
во BeforeProperties и AfterProperties, if the both values are null then the event is triggered by check in else the event is triggered by other actions.
ако (properties.AfterProperties[“vti_sourcecontrolcheckedoutby”] == null && properties.BeforeProperties[“vti_sourcecontrolcheckedoutby”] != null)
{
//This is when the update event is triggered by check-in.
}
на друго место
{
//This is triggered by events other than check-in action.
}